pugslyyy
Expedition Vehicle Engineer Gal
Firematic provided the following backspacing information for their wheels:
Backspacing for the front wheels are 9.5”
Backspacing for the rear wheels are 3.5”
http://firematic.com/fireshop/store1.cgi?p_id=RIK10B195&xm=on
So I would venture to guess that you could also order your Fuso backspacing between those two numbers when you are ordering your lug pattern.
I'm sure that they are running difference backspacing for the tracks to line up on 2005 and new Ford F450/550 trucks they modify.
By my math (which could be very wrong), 9.5 front / 3.5 rear will track (outer edge of rim) 74.5 front / 76.9 rear (assuming 11.25 rim width).
