How to set rear axle height? s10

[b-mac]

I'm working on my 49/s10 swap. I bought a 8.8 Ford Rear end, and a universal triangulated four link kit.

I need to figure out exactly how far to come down from the frame for the rear axle.

My thought was, if I could find the center-line for the front spindles, from the factory, then I could subtract my front drop components (2” drop spindles, ½” taller ball joints, ½” for LS weight difference?). From there, I do the math to move the rear axle to the right spot.

I have these dimensions:
https://www.gmupfitter.com/publicat/...B/LDPDF/ST.pdf (pg 35 of 63)

If you follow my math above, and note that the top of the highest part of the rear frame is 10.40" above the normal top of frame (500), and subtract my 3"ish front drop, you're left with 7.4 down from the top of the high part of the frame. Or 3.4 down from the bottom of the frame to the axle center. Then subtract 1-5/8 radius of the axle... Seems like we're getting too close.

Maybe the real question should be: people with s10, 3" rear drop blocks, stock frame; whats the distance between the top of your rear axle and the bottom of your frame?