UTA LS

I just purchased a relatively low miles 1st gen LS400 and I'm looking into getting a set of 19x8.5 up front and 19x9.5 out back. I have a local guy that can cnc machine me any pattern I want and do any offset, but I can't seem to find a clear answer on what offset to get without having to do major rolling/pulling of the fenders. The car will be lowered 1.5" if that makes a difference. I'd love to have a killer lip with that setup with the lowest possible offset. I will still roll the fenders some but I'm kind of leary of pulling fenders with 12 year old paint.

ATSOU

19x8.5 +38
19x9.5 +38