It's a lot easier to assemble everything on the workbench and then put the finished assembly on the car.
This was a good time to upgrade the wheel-and-tire package on the Sport, but after trying a couple of different wheel styles on the car, it was decided the steelies and "dog-dish" caps looked good on the car, and it's cheap. So we called Stockton Wheel and ordered a set of steel Mopar wheels for the rear with a 4 1/2-inch bolt pattern and a 3 3/4-inch back space. The hubcaps were another gift, but we could have stayed with the older style we had. Since we were upgrading wheels to bigger bolt patterns, we also ordered 15-inch wheels. The 14-inchers just don't seem to fill the wheelwells enough; a 15-inch wheel is almost a must on these cars.
Tires would be another issue. BFGoodrich always seems to be the choice of tire for musclecar guys, so we decided to go that route. Wheels and tires will set you back about $500, which could vary depending on your tire shop.
All-in-all, the swap took us only a weekend of our time. That includes painting and rebuilding everything that needed it. So for around $870, we made the Dart safer to drive, look better with larger wheels and tires, and improved the performance since our 8 1/4 rear has a 4.10 gear in it. So what are you waiting on; the swap is easy.
Place the upper ball joint in the spindle and then install the nut. This will hold the spindle assembly in place so you can place the jack under the lower control arm and jack it up, inserting the lower ball joint into the lower control arm. | 
We have heard of guys using the stock, drum-brake distribution valve, and simply changing the master cylinder for this swap. It's not recommended to do that, which is why we suggested you grab the prop block from the salvage yard. You will have to "tweak" the lines a little bit or even replace them to install the block, but it's the right way to do it. If you don't have a factory disc-brake prop block, you can use an aftermarket unit. We mounted ours down on the framerail, out of sight. | 
When the front was done, we next removed the puny 7 1/4 rear. This was easy. unbolt or cut the u-bolts (they need to be replaced to a larger 3-inch size anyway), unhook the rear shackles, driveshaft, and rubber brake line, and out it comes. |
Our new 8 1/4 rear came complete with longer studs and a neato, shiny rearend cover. Now if we can only get the car owner to keep it clean, instead of this author having to climb under the car every week. We gave the rear a quick coat of rattle-can black, and in it went. | 
The first set of wheels we tried were Weld Draglites that we had, which were taking up space in the storage unit. | 
The wheels looked good on the car, and the tall, 255/70/15-inch tires filled the wheel opening. But we decided to try another set of wheels. |
Next on the agenda was to try a set of Magnum 500s that were from another car. We're not sure why, but the owner didn't seem to think they looked right. All four tires were 225/70s. | 
Before we changed to the disc brakes and larger bolt pattern, we ran steelies and dog-dish caps on the Dart. We had grown to really like the steelies on the car, so we ordered another set-this time in 15-inch sizes. Our wheels are from Stockton Wheel, and the fronts are 15x6 with 3-inch backspacing, and the rears are 15x7 with 3 3/4 back spacing. The tires are BFG radials, measuring 195/60 up front and 235/70 on the rear. | 
As you can see, the sizes we chose place the wheel and tire directly in the center of the opening. |
We finished the look with a different set of dog-dish caps than previously used. The red stripe matches the car better than the other Dodge caps with black trim. | 
Here you go. We took a forgotten Dart Sport, made a respectable driver out of it, and are currently driving the wheels off it. it cost us a grand total of $4,891. Anyone can do this. you just have to be willing to get dirty and do a lot of looking for the right car. |  |