bought this to fix fuel drain back problem

Damn.... I have been trying to fing the part# for one of those for a while...
I need another for my 6-pack 70 Charger and another to install on my 68 fastback.

You sir are a wealth of info !

Careful, as those are the "opposite" of the 6pack originals. The original 6 pack stuff had the orifice port on the bottom as they had a standpipe inside going to the top. These must have the 1/4" port at the top of the filter.