I cut out all of the oil tank holes using the McMark method and hole sizes (which BTW, worked GREAT). I put the tank in and can get one stud through but not the other. Seems to be hitting on something near the door jamb. I tried taking a look with my inspection camera but it was too tight to get it in.

This is a '74 which may have reinforcement plates that an earlier car did not. I swear I read on here where someone else had a similar problem and needed to grind something away. Before I got nutzo with the die grinder, I thought I'd ask!

BTW, I'm using a Patrick aluminum tank.

I think that the 75+ cars had a door frame reinforcement. Not sure if your 74 has it though.

My tank slid right in to my 74...

Do you have any pictures from inside the fender Eric? Did yours pull right in flush with the wall?

Look up there and see if there is some foam that needs to be removed. If I recall I had the same problem

Hey, put some heat shrink tubing on those wire loom clamps. Damn, get you away from a caliper and the workmanship falls off...

here is the thread on the topic, seems to be a 74 too. thread

Yes! That's the thread I was looking for and yes, I do have that bracket. It's the only thing the tank could be hitting on. Depending on how I fiddle with the tank, I can get it close but then the stud doesn't line up with the hole. I'm guessing that Eric's tank fit due to manufacturing tolerances with the Patrick tank. If my tank were 1/4" narrower at that point, I bet it would have slid right in too.

I'll get to the later.

I have flares if that makes a difference. Mine jus slid right in.

That was an early picture Paul. Rest assured.

Turns out the problem was twofold. The support plate did need to be trimmed, but there was some excessive seam sealer where the rear fender meets the door. The Patrick tank runs very close to that interface. After removal of the offending material, the tank fits.

Thanks for all of your help!

Mine was hitting the nut and stud for the trim piece on that part of the sail panel. I had to remove the stud and mount the trim in a different way.