Float in Gas Tank

I used the sender w/ 3/8" exit and 1/4" return, cost $45 on ebay (A-1 Auto or such). Your original was 5/16", not 7/16". Two tips:

1. Re-use your original lock ring. The new ones aren't thick enough and are loose. If you do use it, try bending the ears more and/or using 2 rubber gaskets.

2. With a Walbro EFI pump, I measure 9 psi return pressure thru the 1/4" return tube, which is excessive. The Holley Projection manual specs <4 psi or such. That is using the factory 5/16" tube for return. I suggest flaring the return tube on both ends to lower the pressure drop.