Now that's what you call deep dish wheels, those backspace measurements are tiny.
Are they definitely reverse mounted wheel version as per your photo e.g. what is called soft lip?
Or are they traditional rim design, front mounted. e.g. what is called stepped lip?
They would fit my GT40 if we could graft an extra:
Rears: 2.5" into the rear backspace, so I end up 18 x 12.5" & 6" backspace.
Fronts: 1.5" into the rear backspace, so I end up with 18 x 9.5" & 6" backspace.
Well why not, that's how they make a lot of the wider than 10" hoops, they just cut and shut two hoops together.
Got to make a decision about my GT40 wheels soon. I really want to run 18 x 10 & 18 x 13", so that makes things a little difficult. I've also got to clear some rather large front brake calipers, so that makes things extremely difficult, as Spookypt has found out. High caliper clearance Billet wheels look to be the best option.