Post '65, you'll have issues of modifying the integral crossmember and fitting a rack conversion. Pre '66 there'll be the clearances XE mentions, plus the need for a custon crossmember and R&P steering. Expect to modify the diagonal upper braces, possibly to bolt-on tubular fabrications. A DOHC turbo will be nearly too tight on a pre '66, perhaps an M-II type kit could ameliorate things.
The other big issue, I understand, is cracking the EEC/Smartlock on the driveline in order to best run it. A Wolf or similar could control a non-VCT motor easily, but that's not your bag, judging from your post.
Adam.