if it runs great, then just get a baseline: compression test, leak down, visual on the cam situation (hyd or solid) check the lift. from there you can focus on tuning and eliminating the "fumey" situation.
if you pull it and open it you'll let the magic out and then be left with an empty wallet.
I'd do the above and roll while building a another motor on the slow boat, picking up deals along the way to make it happen.
then again, it depends on the time line for paint and body work... might have some spare time on your hands.