This is along the lines I was thinking of. I think I need to start looking for some sapre 67/8 parts>.....If space isn't a concern (as it was in my case) I would reused the 65/66 towers and try to relocate the 67+ LCA's as inward as possible without hitting the oil pan. Might need some custom brackets and a custom length LCA. Could still adjust UCA using shims if you didn't want to recreate the 67' variable LCA mount (Personally, I'd do the slotted inner mount upgrade and use the 67+ style and an eccentric.)
The steering wouldn't be too hard to figure out. Use the 67+ idler arm, centerlink, and a couple of tie rod ends. Use a 67+ manual pitman arm to mount to the 65/66 1" shaft when using manual steering. Might need the 67-70 spindles for correct tie rod location.