I put a Spectra Premium Fuel Tank in my 69 Nova, with a real GM sending unit, and haven't had any problems with it. I got mine from Ground-Up here in the east, but I'm sure there is somewhere on the west coast to get them. The sending unit I have is an L-78 type with one 3/8 fuel line, no return line. Yours would be different with the return line, and you may not be able to get a GM sender.
https://www.ss396.com/nova/XT-46A.ht...pe=nova&year=0
https://www.ss396.com/nova/XSU-016.h...pe=nova&year=0