but you have to keep in mind that shaft diameter isnt guaranteee that its stronger than another axle model just because it has a little smaller diameter shafts, theres other weak points such as gears strength(thickness) and with soem ratios usaully lower deeper ones that there is lots less tooth contact area, and some models have smaller pinion stem diameter, etc
theres alot to find out and consider and with anything else there will be tradeoffs
mopar used 8 3/4" and dana 60 axles, 3.54 was extremely common, gm ford chgrysler all had 3.54 very commonly, mostyly trucks though, but alot of chrysler cars too yeah, earlier ones
yu never see any big old chrysler cars that would have either axle model under them here, very rare, i have no idea what a chry 8 3/4" looks like, have yet to find such a car to look under, anywhere
good luck