I'm delighted that my initial newbie question has elicited such great responses. It's revealed to me a couple of contentious areas, 2+2 vs 2only, import vs UK.
For me, I would rather spend a year with the mig, some hammers and dollys, restoring an otherwise scrapped Z, than import and convert just to be on the road sooner. That's just me.
That said I have become extremely wary now that so many have mentioned poorly aligned body(structural)/chassis. I think buying a car that was bent out of all use would be the biggest fear. Do these cars get out of shape from 40 years of collisions, or does the rust turn them into jelly? Is it the uni-body, the chassis rails, or both?