This probably doesn't help here but on my 4.9L/4T60e I used a driver side (4 speed) stick axle on the passenger side and an driver side auto Pontiac 6000 Left axle on the 4T60e driver side. Seems to fit fine.
------------------ " THE BLACK PARALYZER"
-87GT 3800SC Series III engine, custom ZZP /Frozen Boost Intercooler setup, 3.4" Pulley, Northstar TB, LS1 MAF, 3" Spintech/Hedman Exhaust, P-log Manifold, Autolite 104's, MSD wires, Custom CAI, 4T65eHD w. custom axles, Champion Radiator, S10 Brake Booster, HP Tuners VCM Suite. "THE COLUSSUS"
87GT - ALL OUT 3.4L Turbocharged engine, Garrett Hybrid Turbo, MSD ign., modified TH125H " ON THE LOOSE WITHOUT THE JUICE "
[This message has been edited by Dennis LaGrua (edited 05-06-2021).]