I've read (here) the front ends upto early 80's will bolt in, with an extra hole or two.
Joe, I'm curious. I haven't noticed any real understeer in my C20s. Did your trucks have an antiroll (sway) bar on them. I had a Volvo P1800 that almost killed me a couple of times when it plowed into corners, but then I don't try to imitate Sterling Moss anymore either.
Larry
68 C20 327 daily driver
63 C20 292 Camper truck
65 C10 ? Custom Cab AC,PB,PS,$flasher