Trayback Build

Hi all im wondering if anyone can help ..... my partner is looking at tray backing his 3dr disco due to rust and rot however he would like any info he can get from anyone who has dome this or knows alot abt these builds as he has a rough idea of what to do and how to go abt it but there are some things he would like to make sure of first so if anyone can help then fibe me a shout either on here or look for me on facebook JAX BACKHOUSE thank u for your time.

Search on here there a few that have been built and are still been built