Well, more good news.
Started gutting what was left of the interior of the Cougar and found way more rust--not just heavy surface rust but holes and super-thin areas that you can push a finger through. It's creeping up the firewall, the passenger side A pillar is pretty junky, found holes in the roof above the windshield, inner fender splash panels falling apart etc. etc. etc.
I've decided to throw in the towel on this car and have put it up for sale.
So now, I have a nice 410 going together and no place to put it.
Been scanning CL and FB marketplace for another suitable Ford or Mercury 2 door car but anything not needing a ton of work is way out of my price range.
I suppose I could revert back to installing it in my '89 F-150--which is what the original plan was--and would make the most sense from an economical standpoint.
BUT, I am planning a 521 stroker build for the '74 Cougar. The 460 that's in it now I built last year and has about 200 miles on it, if that. It would make a nice engine for the F-150 and would be period correct.
If I went that route, then I guess I'd put the 410 stuff up for sale.
I don't know. I'm just feeling a little bummed and defeated at the moment.