[Shane]

I third the 29" center-center for the front, the rear is more but I don't know it off the top of my head

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Hush newbie!

 

[Shane]

Converting from that pic yotacowboy posted the rear is 39 3/8" on center, I can verify this later this evening if nobody else knows for sure.

 

[Shane]

Looks like it's actually 39½"

 

[Shane]

My rear measurement of 39½" was directly off an '87 axle that I have sitting in the garage, but always good to get a second opinion.