Bullit Wheels 17x8 45mm offset - how to fit?

First of all, I have a '74 Duster with an 8 1/4 rear and, power disc brakes, and a 3 speed manual (on the floor) that I'm trying to get back to being road worthy from being mostly a drag car (I recently bought this).

I've read a ton of threads regarding the Mustang bullitt wheels. When I saw a set for cheap, I figured I'd pick them up. They came off an '06 Mustang.

I know it's not a completely bolt in installation and that I'd needed to make some modifications to make them fit. What I didn't know is that there's apparently two different offsets.

I has assumed these were the 5.72" back spacing wheels, but they're not. They have more back spacing. Apparently, they have about 6.2" of back spacing.

Long story short, how do I get them to fit? Or, should I sell them?

What I "think" I know:

1. Rotors will need to be machined so the hubs fit inside the wheel
2. Need a wider axle or spacers to fit in the rear.

I do hope to upgrade the rotors to 11.75", but I don't know if those hubs will fit inside the wheel or if they need to be machined as well.

As far as the rear is concerned, I don't know if running 1 to 2 inch spacers is practical. Upgrading to an 8 3/4 inch axle is doable but also opens up another can of work with the proper u-joints, drive shaft length, etc.

Not sure if my current drums can swap over too. But, it definitely would be an upgrade and it looks like traction devices (TrueTrac) is less expensive for 8 3/4 vs 8 1/4 axles.

I have to admit, when I mocked the wheels up the car looked great!

Thanks!