I have a GSS315 sitting on my coffee table, neatly cradled in a FACTORY gvr4 fuel pump housing. The 341 should work fine.
I have a GSS341 sitting (brand new) right next to the assembly. It looks identical, and should drop right in. No worries.
I'll pull the FACTORY-STOCK pump assembly out of 555 tomorrow afternoon and compare stock vs what i have here. I'll take pictures and post them as well.
It looks like i may have done a little bending on the tube to get this pump to work, though. It's honestly been so long, i can't remember. I'll be sure and post something that will show any differences in mounting in detail.
EDIT: after looking at this link, it appears as though i must have bent the tube from mounting plate to pump, but it still worked out ok
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