I've worked extensively with short cases in leverguns, mostly with the Cowboy .45 Special, which is for all intents and purposes a .45 ACP with a Colt rim. AAMOF, before we digress further, if I was loading for WB, I'd load my pistol ammo with ACP cases, switch out my shell holder to the Long Colt size, swap out two small, easy to change bits on the feeder, and fill the case feeder with Cowboy .45 Special brass, and continue....
But to truely run ACP at speed in a levergun presents several problems. it has been done in both marlins and'92s, but NEVER reliably enough for the kind of operation CAS demands.
If I was gonna HAVE TO do it tomorrow, I'd take a'73 chambered in LONG COLT, have the barrel cut, threaded, and rechambered for ACP (of course the mag tube would need to be cut to match), and install one of my Cowboy Carriers specifically designed to run the short rounds, and I'd be in business.
But I don't find using two different cases objectionable when it is as easy as swapping the shell plate and two feeder bits on the 650.
yer Marlin is gonna be a lot tougher, and less likely to succeed at speed, frankly.