I would suggest asking Lanner at
www.vdubengineering.com , or ask him in his section on here. The later rears will not bolt-up to the early hubs without some mods. The e-brake shoes would be a problem, and to offset the rotor enough to line-up the e-brake shoes, you would put too much side load on the hub bearings. If your wanting to add track use the ali trailing arms.
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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