I imagine it's possible to get it on square to the existing threads, but I'm pretty sure I removed that front float bowl and did it in a vise where I had a straight shot at it and gravity on my side.
Easier to make certain it is clean and free of any tapping debris too.
I don't recall what I used for a filter back when I still had the 4180.
My newer carbs all have right hand feed and I am using a bigger metal filter with 8mm ends and a 90° sweep on the outlet
Jim,
Lil'Red is a '87 F250 HD, 4.10's, 1356 4x4, Zf-5, 3G, PMGR, Saginaw PS, desmogged with a Holley 80508 and Performer intake.
Too much other stuff to mention.