Hey Ryan,
That's a really cool fuel pump. �You don't see a glass top with vacuum very often. �
I don't know about your specific pump, but I believe the rule for CJ3A pumps with vacuum wiper function is a spacer should be used. �It helps reduce the fuel pressure. �It also helps the pump fit better in behind the front engine mount plate.
You can use additional gaskets, but I made my own spacer. I had a chunck of 3/16" steel. I used the pump mounting surface as a template, then cut, drilled and polished. Turned out fine.
Tim