Hola Amigos -
Do you mind if I rest a little bit on the beach...?
-MLO was often leased to FTL as their passenger aircraft for military "MAC
charters" in the 1980s, and got fitted at one time with JT9D-70A engines, as FTL had inherited with their merge (SWA) of a few 747-245F which had these engines. That was before my start here in Argentina...
The JT9D-70A reversers have bad reputation, some operators went as far as asking crews not to operate reversers unless absolutely necessary.
Correct, Atlas converted some of their P&W 747 with GE
CF6 engines. To do so they acquired some old ex-ANA 747-181 parked in the desert, took their engine mounts and struts to convert their P&W powered 747 to CF6 engines. This is the only airline that ever did such major change.
Aerolineas operated a CF6 powered 747 airplane at one time, it was on lease, in the early 1990s, from Varig... Nice engine, like it much (personal opinion).