need help with 8 3/4 shortening measurments

[426 dart]

so im almost done with mini tubbing my 70 dart swinger and im in need of the proper measurments for shortening 8 3/4 rear end and axels im going to move the springs to the center of the frame rails my plans are to run the widest tires possible and in hopes of putting 17x12 rear wheels so for those of you who have already done so...any help with measrments would be appreciated

thanks
Dave

 

[pettybludart]

Here,s a quick way I did mine(narrowing)for 15x10inch rims.

O.k..stock a-body width is 52 5/8 inches flange to flange.I took a C-body housing and cut to 46 5/8.Basically 3 inches off each side.To run a 10inch rim with minitubs you need 7.5 backspace with a stock A-body rear.So I subtracted the 3 inches from each side of A-body width,allowing me to run a 10 inch rim with 4.5 inch backspace.This isn,t the way everybody does it,but it worked for me and had enough room for a 15x12 rim(4.5 b.spacing) with a 29 inch tire.Hope this helps?LOL
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