modifing seat's

[jd4300fel]

I just recently bought a 3rd row yukon seat, I should of bought the second row seat. so now I have a seat that I really like but does not fit my truck it' ten inches too narrow. other than selling which is an option what can I do to make the seat fit. I am thinking of taking the seat apart and add ten inches to the frame. then finding foam and molding it to the existing foam. has anybody done this? any tips? and sources for springs and foam

thanks