biggest wheels and tires possible

[RICH MUISE]

Now that's a good upskirt shot!! Is that your's Tom?? The '58? looks great...we don't see enough pics from you. What are those tailights? Got some more pics?

[57dohc]

The 2004 Mach 1 wheels (17 x fit perfectly on the rear of my 57 Custom 300.  Tire size is 245 x 45 x 17  and they clear the fender lip by almost 2 inch and the inside spring leaf by about one inch.  This was measured to the tire bulge on the sidewall.  These wheels do have  a 6 inch backspace.  I would consider using them but the front wheels look like they won't work with a backspace of over about 4.5, making a match impossible.  The largest backspace  I can find on the internet for a 17 inch wheel was 5.45 which would probably work with the same wheel ordered with a smaller backspace in the front.  All measurements were with the stock rear and front spindles.  Changing to Granada spindles and discs may change the front clearance to the upper ball joint which I will have to check when I get that completed.

[RICH MUISE]

I assume those Mustang wheels have a high positive offset, moving the tire too far INWARDS. If so, how about a spacer/adapter?
https://www.uswheeladapters.com/Services.html