Axle WMS difference

Would it be bad to have a front D30 at 63in with spacer and a rear Ford 9 at 66in WMS?

I'm just finding it hard to justify all the extra time and money just to take 3 inches off the rear. If anything this means I need to build a front end that is a bit wider then back space the tire a little. It seems this ford 9 isn't quite a full size rear, correct?

There are a bunch of Ford 9" widths available on stock vehicles, depending on make and year. Look for a 31 spline variant. Here's a chart for Bronco's and Pickups:

WMS to WMS

• 57-72 F-100 Pickup - 61 1/4"
• 73-86 F-150 Pickup and 78-86 Bronco - 65-65 1/4"
• 66-77 Bronco - 58"

I have a 31 spline from a late 80s F150 I bought just for the center section to use in my original 9 housing with currie shafts. Well..... Turns out that housing will bolt right in it seems. Leaf outside measures 47in and leaf perch on the housing is 47 outside as well.

May be able to put the 9in this weekend now that I know it will fit.

Typically you want the rear axle to be a few inches narrower that the front. This helps with turning radius and tracking.

I'll be taking 2 inches off each side for a total of 4. With this I only need to cut one shaft down.