Will it be in the way?
ABS would be quite handy on a rear of a truck
If it's not in the way you can just unplug it (someone correct me if I'm wrong).
It'll still continue working but won't be proportioning between the 2 rears.
I think these only had rear ABS? (again correct me)
So it shouldn't affect your front/rear proportioning.
Looking forward to the project
the proportioning valves are in the abs module as far as i know...but unplugging the power to the motor shouldn't have and effect on normal braking. But if the whole apparatus is in the way...just get the routing, figure out which line is which and take the whole thing out and put in a variable valve...they are cheap enough...just have to play with the adjustments to get it set just right.