If you do the labor yourself then it will be about $500 or so, including rebuilt stock IRS tranny. You can get alot of the parts from www2.cip1.com in Canada. If someone else does the labor $$$$$
. The more you can do the cheaper it will be on labor. Ideally you should give the person doing the work just the pan, weld-in mounts, trailing arms, torsion bars, torsion end caps,and spring plates. The hardest part of the swap is alining the trailing arms for propper camber and toe in before welding everything up.
I have the entire stock IRS set-up on the floor in my shop right now. I went the late model 944 ali set-up with 944 torsion bars, end caps, two piece spring plates, axles, CVs, trailing arms, and turbo brakes.
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1970 T1 W/MassIVe 2913cc RAT/?EFI? w/direct fire (very soon) and 915 trans
1962 SC 1776cc SP 944NA brakes, 993 wheels
VKG