68 Camaro - 18" Wheel Fitment Question

[bigboi]

Hi,

First off... I am new to the board. This looks like a great place with a lot of information. Glad to be a member!


My Car...
I have a 68 Camaro RS/SS Big Block that has been restored with all stock suspension and sits at stock ride height.



My Plans...
Suspension:
DSE 2" Drop Front Coils and DSE 3" Drop Rear Leafs.

Wheels:
Torque Thrust II Wheels
Rear // 18x10 // 275/40/18 BFG g-Force KDs
Front // 18x8 // 245/40/18 BFG g-Force KDs

My Question...
What backspacing will I need to go with for these wheels? Will the tire size I have listed above work? Can I go wider on front tires w/o rubbing?

I am sorry if this question has already been answered somewhere on the board. I have looked around a little and have not found any solid answers related to the setup listed above.

Any help is appreciated! Thanks!