With Jeeps? Anything from the Willy's era, maybe. But the AMC era? Don't know about that.
Get into the 60's and 70's? Or even the 80's? Not really. What's a purist to do with his Buick sourced V6 or the Chevy sourced 2.8L? Or the Chrysler and GM transmissions? The NP (Chrysler) sourced transfer cases? The Dana's front and rear? The Ford ignition systems? The GM brakes?
Except for the engines and the final assembly there's not a lot that AMC could claim for purists to grab on to. It's a Jeep forum, not an overall AMC forum which would include Nash, Willy's, AMX's, or S/CRamblers.
The only time you might here someone gripe is if a 4.0L is replaced with something different, but Jeep lovers are so in love with the 4.0L already that they'd rather build those than replace 'em with something different. Hell, the 4.0L has become ubiquitous with the go-to engine that you see it being used to replace 258's, etc.