8-1/4 Rear Axel Question...HELP

[72RoadrunnerTyler]

I'm about to buy a 1977 Dodge D100 8-1/4 (3.55 SureGrip) rear end this afternoon to replace the 8-1/4 (2.73 Open Diff) in my 72 RR. I know that the spring perches need to be moved, I'm okay with that. I also know the housing is slightly longer than my b-body. Based off dimensions taken from the owner flange to flange his rear is 58-7/16" and mine is 57-7/8" so close enough. My question is can I use this 10 bolt truck rear axle assembly with my setup? Is there a difference in truck 8-1/4 vs passenger car? Thinking I'm okay but would like some reinforcement from someone who may know. Thanks!

Yes a 8-3/4 would be better but don't have the $ or connections to find one locally..

Pic of truck rear

 

[Kernel Sanders]

yup just the perches relocated. Ebrake cables from the truck maybe way too long but if your careful you can reuse the ones from your car... or just swap over the whole brake setup but that will mean opening up the case for the c-clips and axle removal

Oh maybe the yoke/ujoint sizes... if they are different there are conversion ujoints available

 

[dvw]

Just make sure to mock up the housing in the car with the perches just clamped between the spring and housing. Have the weight on it on the ground to verify pinion angle. Many body's are off slightly one side to the other. Now is the time to slide the perches slightly to one side for max tire clearance. My Challenger is offset 1/4". This made a 1/2" move at the fender lips, looks much better.
Doug

 

[72RoadrunnerTyler]

yup just the perches relocated. Ebrake cables from the truck maybe way too long but if your careful you can reuse the ones from your car... or just swap over the whole brake setup but that will mean opening up the case for the c-clips and axle removal

Oh maybe the yoke/ujoint sizes... if they are different there are conversion ujoints available

Just make sure to mock up the housing in the car with the perches just clamped between the spring and housing. Have the weight on it on the ground to verify pinion angle. Many body's are off slightly one side to the other. Now is the time to slide the perches slightly to one side for max tire clearance. My Challenger is offset 1/4". This made a 1/2" move at the fender lips, looks much better.
Doug

Thanks for the input gents. I had anticipated a possible u-joint change as well, that's no problem. I'll definitely dry fit the perches to the housing to justify pinion angle, read a few threads on that process. But nice tip i didn't even think about offsetting the perches to max. tire clearance. Note taken, thanks again guys

 

[67belvedere/225]

I installed a dodge diplomat 8 1/4 onmy belevedere from a police car , it has the big brakes on them
I made a clean swap with some modified brackets in the back it went well for me
I see if I have pictures at home

 

[67belvedere/225]

this is my rear. i went up a size on u bolts and faced some spacers .