Rim backspace for 1967 Barracuda

Guys,
I have a few questions on rim backspace for my 67 Barracuda. Car has
stock drum brakes, stock 7 1/4 rear, and stock 4 inch bolt pattern all the way around.

(1) what is the "maximum" backspace that I can have for rims on the
FRONT of the Cuda (I had heard 3.25") without clearance problems,
i.e. rubbing, brakes, etc ???

(2) what is the "maximum" backspace that I can have for rims on the
REAR of the Cuda (I had heard 4.25") without clearance problems and
without relocating the rear leaf springs ???

(3) I plan to add bolt-on 1 inch spacers (to change to 4.5 inch bolt
pattern). Can I then add one inch to the maximum backspace for both
the FRONT and REAR rims (for example 4.25" max on FRONT and
5.25" max on REAR) ??

(4) I'm looking at ARE 17 X & inch rims with the max backspace I can
have and 225/45/R17 tires (25" height; 8.3" tread width; 8.9" cross
section) all the way around. Does anyone see any clearance or fit
problems with this setup?? (I would like to lower the car an inch or
two if possible)

Any help is appreciated.
Thanks for all the help I get from this website. I haven't had the Barracuda long and I'm still getting up to speed on all the technicals.

Thanks,
GLJPLC