Originally posted by InTheDogHouse50:
Say I get small block 350 and the TH200-4R - can I keep the stock rear end?
Not easily. Your current rear is the torque tube type, and adapting that to a modern automatic transmission is a challenge and if anyone makes a kit to do it, I've never seen it.
I've got a '73 Chevelle rear under by '55 1st, which would be the same as your truck with one significant exception. My truck was open driveline from the factory. The Chevelle rear needed to have the coil spring brackets cut off, and spring perches welded on.
Even if you use a rear from a leaf spring car you'll most likely need to move the perches, so the process will be similar. Also the spring bolt that is used to locate the axle is not at the axle centerline on your truck. If you buy a set of Mopar perches (lots of guys suggest that) you'll need to drill a new set of holes to locate the axle. I've heard 1-1/2 to 2 inches forward of the stock hole, but if it were mine I'd experiment until I like how the axle fit in the wheel wells. Or venders sell a perch kit ($150 at ChevyDuty) that has the right holes drilled in them.
And then you'll need a driveshaft the right length. You can probably find one in a wrecking yard given enough time. I'd just have one built.
