Maybe this will help?
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....I looked up my order history, this one was made for me by axemasters, based on the nut for an Ibanez SR-series 4-string, I think, since the only Epi ones he had pre-made were for the wider bolt-on 'birds.
The SRs have mostly the same dimensions, just needed to be a bit taller.
View attachment 4830014
.....but, Epiphone uses 1/4" thickness, Gibsons afaik use 3/16" thickness. Should be the only difference though?
Very few places on Talkbass offer such timely and in-depth technical support for questions raised (pics, measurements, supplier leads… great post!) I’ve been in other clubs on TB where you ask a technical question and wait days for a legitimate helpful response (if you even get it).
Kudos to you Kara!