That fugly Toyotastang with the F250 engine and Corvette transaxle again?
To answer your question, buy one and find out. They've been done with both Terminator and Lightning engine swaps (no Coyotes I'm aware of yet), independent rear suspension (other than the blue bastard), a big block Ford with twin turbos (built by Jack Roush himself and approved of by the legendary Gray Baskerville), and every 2.3 combo you can imagine. One guy on Mustangii.net even did an IRS with Jaguar-style inboard disc brakes.
Alcino's "Low Buck Bully" (Popular Hot Rodding gave it that name) is probably my favorite II.
Vegas Stang's silver "Shelby" II was a damn nice build too. It's so subtle. A II guy looks at it and recognizes how little is untouched on it, a non-II-guy thinks it looks mostly stock.
That V10 II was wrecked inside a transport trailer roll over a while back. It is currently being rebuilt with different tail lights (I think 71-73's) and engine combo. Can't wait to see the new version.