In our case, we found an F-Body short-extension overdrive 833 four-speed in an Aspen R/T at the junkyard. The 318 four-speed car was complete, yielding a mother lode of conversion pieces. For our A-Body application, the F-Body's short-extension tranny, bellhousing, shifter and linkage, flywheel and clutch, and shift fork were a direct interchange. We pulled the clutch linkage as well, which wasn't an ideal match for the A-Body chassis, but beggars can't be choosers. We knew with some minor, though well-thought-out changes, we could probably adapt the linkage and fabricate the rest of what we'd need (if hammer forging your own linkage parts against an anvil isn't your game, get the correct pieces for your specific application). We had already pack-ratted the correct A-Body pedals from a local car-show swap meet, so the only parts missing when we got ready to start were the tunnel hump and carpet, easily obtained by calling Sherman & Associates for the hump, and Auto Custom Carpet for the rug. The only thing between us and tire-screeching shifts was to break out the cutter, welder, and wrenches, and cram it in. Here's how we did it.
The 833 four-speed has the...
The 833 four-speed has the same mounting configuration as the automatics, so the same crossmember and mount will bolt right up. The trans is fully bolted in place before we make the final alignment check of the hump.
With the trans and shifter...
With the trans and shifter in, the hump is lined up again, making sure the shifter pokes through in the right place, towards the back of the hole, and centered right to left.
The final cut is about 1/2-3/4-inch...
The final cut is about 1/2-3/4-inch inside the marked outline of the hump, giving the required overlapping flange to weld to. Note the guidelines that are marked to make this cut accurate; this is not a good place to mess up. Here is the finished opening; the edges of the cut hole should be painted over with Resto-Motive's POR-15 or other rust preventative.
After trial fitting, the Sherman...
After trial fitting, the Sherman & Associates hump is MIG welded in place. It's nice to know everything will line up exactly right. Notice a small sheetmetal filler section is added to fill the gap at the rear of the hump, although a thick caulk or bondo could be used.
The edges of the hump are...
The edges of the hump are sealed with 3M Brushable Seam Sealer, which is remarkably similar to the factory stuff. Looks pretty good.
Here's our clutch linkage....
Here's our clutch linkage. The service manual for your car gives a detailed breakdown of the parts involved with any particular body or platform, though the basics are all the same; it is always a good idea to have it available for reference. We used the pieces scavenged from the F-Body donor car, which requires cutting off one of the bellcrank arms and "re-clocking" it, and re-drilling the bellhousing pivot to move it in line on an A-Body. The pushrods are fabricated. Obviously, the correct A-Body stuff will bolt right in. Year One has much of the required linkage available new for some Mopars.
With the hump welded in, it's...
With the hump welded in, it's time to install the four-speed for real. The clutch fork pivot (arrow) is bolted inside the bell housing; make sure the pivot is sound, since they crack and break. The bell is then bolted to the back of the block. Any of the old Mopar service manuals detail how to check the bellhousing alignment, which is a good idea.
Next the trans goes in to...
Next the trans goes in to meet the bellhousing. This is a two-part operation since there isn't enough room to swing the trans and bellhousing in as an assembly without hitting the pinch weld on the floor pan. Note the disc-brake rotor support under the trans.
The outer pivot point for...
The outer pivot point for A-Body clutch linkage is through the inner fender, just above the left framerail. The hole is already in the sheetmetal, but it won't survive one step of the clutch with-out the required reinforcement bracket, which welds to the framerail. Fabricate the bracket out of some 11/48-inch sheetmetal, turning up the edge to box it out like the stock piece, and weld it up.
Here's the finished linkage...
Here's the finished linkage as seen from above the brake booster. The bellcrank needs to be straight across, with the pushrod in line with the clutch fork. A boot is required in the firewall where the pushrod goes through. We sourced a new one from Year One.
The automatic's neutral safety...
The automatic's neutral safety switch wiring was cut off at the factory three-pin connector. The outer wires are actually for the reverse lamps, and were connected to the four-speed's reverse lamp switch with a couple of common female spade connectors. The middle wire is the relay ground for the neutral safety switch. It can be grounded or wired to the clutch pedal interlock switch if the car is so equipped.
Short-extension 833 four-speeds...
Short-extension 833 four-speeds are the same length as a 904 TorqueFlite, though all splined-output 833s have the large 727-sized output splines (except for some '67 short trannys). The driveshaft yoke will need to be changed to the large-splined version from a 727 or 833 if swapping from a 904. The yoke can be found in either large or small U-joint versions. 727s and long extension 833s are 3.81-inch longer, so the driveshaft needs to be lengthened a like amount.
Underneath, with the clutch...
Underneath, with the clutch linkage, shifter, wiring, driveshaft, and speedo cable all hooked, as well as the two front splash shields bolted to the bellhousing, the swap is done.
Cleaning Up the Column Up...
Cleaning Up the Column
Up top, we still had the stock automatic column-shift steering column. It could be just bolted back in with the shift stick removed, or we could have searched for a '67-'69 (dash ignition switch) A-Body power-steering (manual-steer columns are longer) floor-shift column. Instead, the column was torn down, and the offending protuberances were carefully hacked off the bearing and shift-housing castings. We molded remaining holes in the housings with fiberglass-reinforced bondo (Kitty Hair). It was tricky, but looked perfect when done.
The modified column was painted...
The modified column was painted and then bolted in, looking for all the world like a factory floor-shift column.
The finished job. Time to...
The finished job. Time to go out and run the Dart through the gears.