Guys,
rear belts are pretty easy to do (on an FE anyway), but should be similar.
I mounted my reels on top of the wheel arch. (like an XD falcon).
I used XD falcon wagon reels and belts.
the top mount is done by cutting out a slot in the rear of the pillar,
sliding in a 10mm plate with a 7/16" UNF thread cut in it.
stitch welding the plate in to the pillar. done, mine passed engineering like this.
in this pic you can see where the reel sits.

if you look carefully in this pic you can see wherre the plate is stitched into the pillar.

the belt runs in the narrow gap between seat and body.
Cheers
Ed