I sold my MK II last night and looking to buy a IV very soon. This time I want to go with the I.R.S. but don't want to buy the rear-end package when I purchase the kit. So my question would be can I purchase the kit with and I.R.S. frame with my kit and then purchase the components at a later date? Also I am wanting to go carbed again, does FFR still supply a harness and is it from someone other the what came with my MK II?