Factory AC firewall Pics- 66 Barracuda/ Valiant...

I did this once. Swapped factory A/C into a '65 not originally equipped. It was a bigger, harder, more expensive job—and the result was less satisfactory—than I'd hoped. I could do a better job of it now, because of what I learned, but I'm pretty sure I wouldn't try it again even if I had a complete system at hand.