[Jon01]

Sounds like it's having delivery issues. Has he put a gauge on it to verify it's dropping pressure?

I ran mine all last summer with doubled up regular clamps on the suction side (between pump and tank). No issues.
I would not clamp on the pressure side of the regulator.

If you hurry up and order what you need it could be done in a week easily. I wouldn't skimp, a) you're playing with gas and b) this will easily strand you if something gives up.