285/75r17 wheel backspacing?

Hi all, I have a 2009 Tacoma And i am planning on running 285\75r 17 11.3x33.9 tires On a 17 x 8 wheel. I was wondering if I would be better off going with 4.5 or 4 inch backspacing? From what I have read it sounds like 4.5 Would reduce rubbing on the cab mount, But with the size of the tire I am concerned about rubbing on the front of the frame or in the back just in front of the cab mount. I realize that I will have to chop the cab mount and the wheel well, Fender flares and so forth, but I would prefer not to have rubbing anywhere else on the frame That I can't Cut. I would appreciate any advice. Thank you

 

Stick with 4.5 and happy cutting! Shouldn't rub on frame because you're not going really wide with the tires

 

Yeah make sure you chop it good. My 285s are still rubbing and I did a good bit of trimming

 

Thanks for the replies. Any thoughts on whether these tires would work with stock fj steelies (17x7.5 with about 4.85 backspace)? I have read that some guys here are running 285/70r17 on this wheel with no spacers, And it looks like some of the FJ cruisers are running these wheels with 285\75r17.