I don't have a light gold Challenger photo, but it sure would look very nice with dual chrome racing mirrors and a black vinyl top. and black strobe stripes coming out of the fender moulding! So back to original gets my vote!
And to your question, yes, interior with have white seats, white...
I've seen up to an 1" difference from side to side on a car with factory quarters and axle. If everything is centered and equal, 295 width will fit as @6PKRTSE has on his Challenger. Quality control wasn't very good on our E-Bodies unfortunately. 275 in the rear should fit in any factory E-Body...
Read this. I'll input no more to this post. Longer rods will typically make for a lighter piston (smaller bob-weight) which will typically make more power and the engine wear will be less than a similar displacement engine using shorter rods and heavier pistons...
If it does have an original plastic camshaft timing gear, it only takes one startup from a running car to jump a tooth. Back in the day, my brother and I used to get Mopars cheap that didn't "run" and just needed a new timing set!
I could be completely off, but it looks like the upper shock mount and the rest of the shock is MIA! Perhaps it broke and that was left behind? I base this off you saying it still had the bolt and nut attaching it to the frame.
Funny that Diamond pistons makes a 383 piston to run a stock 440 rod with a stock 383 crankshaft. Don't think they'd bother if there wasn't some advantage to a longer rod.
https://www.diamondracing.net/shop/pistons/bb-mopar-383-piston-kit-4-280-in-bore-1-516-in-ch-3-00-cc-std-pin/
I have 255/60-15 on the old 15x7 cop wheels on all four corners of my 70 Challenger with no issues. Been on there for about twelve years (had 235/50-15 before that).
Almost all of the pictures of the bores show notches. I highlighted one so you know.
Hopefully some of the Hemi guys will chime in regarding which parts are hard to get. But I think my list is a good start. And nothing wrong with a "budget" 426 hemi build!
Mains - 90
Sides - 80
That's the torque for the main cap bolts in ft-lbs.
Obviously the block is notched to allow a stroker crank. Do you or your buddy know the current bore? Stock 4.250" or bigger?
Some 413 industrial engines had the eight bolt rear like the 426 Hemi, but they stick out...