GTA rim custom job question

need advice

I have a set of non-dimpled GTA rear rims and have been looking for a local company that cuts the GTA rims and re-rims (is that a them into a 10 inch wide rim, which i finally found a place in Miami.
they charge $250 per rim. they do 8 inch to 12 inch wide.
The cut out the webbing (center) of the rim and re-weld it into a new "barrel"/rim with the dimensions and backspacing you pick.

My question is does anyone know what would be a good backspacing number that i should do in order to put the widest tire on a 10inch wide rim without having rubbing/fitment issues from the inner wall or outter fender lip. It is only going to be for the rear, and also looking for the maximum lips on the outside of the rim. im looking for a wider lip than the GNX rims.

I posted a reply about this in your "FGT ( :biggrin: ) custom rim backspace" thread and also posted a picture...

Claude. :wink: