Rotella is fine in anything with Vortec heads. In the older flat tappet Fords (all Fords) and Chevys, find an oil with appropriate levels of ZDDP such as, but not limited to, Valvoline VR-1 20W50.
Previous: 1993 Prostar 205
Red 1998 Ski Nautique, PCM GT40, 310 hp, , Acme 4 blade, Perfect Pass SG/Zbox.
Be kind. Have fun.