Want to add a fuel pressure sender to the aft end of the fuel rail. Would like to keep my mechanical guage on the front end. Any ideas where to get a fitting to go from this to 1/4" pipe thread?

1/4" close nipple and 1/4" tee available at Home Depot(I know all to well) and probably Lowes

Sorry, this is a 1/8" fitting.

any speed shop should be able to set you up with earles type fittings probably #8 to 1/2 pipe then bushing from 1/2" to 1/8"

Oops . You're right , it is and so is mine
But like I said , any HD.