I like the stock retainer, light, pretty much indestructible and the pressure against it can only make it tighter over time, rather than loosening it.
Lots of conflicting/absent data out there, I must admit. Is it 40 lb/ft for the cap, or 60, or 78....is it fuel to lube or oil, which way is up on the stock retainer button, blah blah, blah.
I used 50 lbs because it's obvious from the fine threads on the cap, 78 is WAY too much, 40 is what AWE recommended but, that's a VW pump. 50 passed the TLAR test.
I lubed everything well with 10W30 synthetic motor oil, figuring that first start up might just be the deal-breaker. Those tolerances are pretty tight and something more shear-resistant and "lubricious" than gasoline should be in there right off. Gasoline should dissolve the motor oil pretty quickly and not cause too much grief downstream, imho, of course.