14 bolt questions

[one_ton_k5]

Hi all, I just finished rebuilding a 14 bolt from a 79 cab & chassis one ton GMC.

I am getting ready to install it in my 71 Blazer and I have a few questions:

The spring pads on the 14 bolt are 40.5" center-center, the spring pads on the 12 bolt I have in the truck now are 40". I am installing an ORD shackle flip and new bushings at the same time as the axle, can this 1/4" per side be made to work without cutting and re-welding the perches?

I do have a welder and I already moved the brake mounting flanges out and converted the axle to disk brakes so I'm not afraid to cut and weld but I'd rather not if I can avoid it. What do you guys think?

Also for you guys who have done this, can I use my rear driveshaft with the hybrid u-joint or will I need a new one?

Thanks. Once I get this axle in I can move on to the D60 up front!