69 corvette
You will need to make a couple of manly dents where the headers contact the steering box. No modifications needed on the passenger side.
If you can get a used set to practice on, that would be best. Mine were painted, so no worry about chrome or ceramic coating coming off.
I pushed them up in place from the bottom and made some marks with kids chalk. then took them out, laid a piece of steel pipe (2" I think) on the chalk mark, then gave it a good whack with a small sledge. Took 3 or 4 ins-and-outs efore I got it to fit.





