Unfortunately, I didn't have to persuade f-body wheels to fit the car. LOL.
It turned out I had 3 old trailer wheels laying around that had to get junked anyway. I think they may have been 5x4.5"(114.3mm) bolt pattern which fit the 5x115mm very closely. Then I managed to find an old temporary spare which was also 5x4.5" or so. So the car is now sitting on junk wheels. Tomorrow I'll pull the hood, fenders, doors, seats, trunk and other random parts and then off to a junkyard it can go.