wheel Backspacing! 22' rims! HELP!

[Westcoastpainter]

hey guys.

so im in the market for some wheels. now i don't have a body on to reference measure what will tuck, so I'm trying to figure out my backspacing as I'm ready to order wheels. ok IM running PB front and rear dropmembers with narrowed arms up front one inch. Also I'm using CPP modular spindles with their big brake kit. Now I'm told the fronts will be ok, they're a 22x8.5 with a 5.5" backspace. I'm thinking 265/35/22 tires

as for the rear this is the one I'm really questioning, 22x9.5 with a 6.75" backspace. I'm using a stock length 12bolt, with disc conversion to the 12" cpp discs. trailing arm kit, inboard bags. i have room for up to a 12" wide wheel from my PB kit. Just not the bank roll for those big billets just yet. so any help or advice would be great help. thanks
derek