" The limbs are mounted on the back of the riser(the side facing me when I shoot). "
Just so we get on the same page, the string side is the belly,odd as it seems! Back is toward target.
Can you take a pic with both bows , it would really help to grasp how this would work.
A 2" longer riser will lighten the weight, probably about 3-5#
I've never used West System, but I do know Smoothon is really good.
The inserts are pretty standard, I have those and the pins too.
If you can get a pic, it will help to understand this.
Anyway we need pics of the rehabbing! LOL :D