These engines are indestructable, as long as you keep oil in them, and make sure the timing chain guides are ok.
They are not at all picky about oil. You can run anything from a 5w30, to a 15w40. Personally I run PYB 5w30 in dad's '86 motorhome, and grandpa's '93 pickup. They seem to love it, and they run very smooth. Especially the camper, it has a hard life pulling 6600 lbs around. They both run great. I'd also choose a quality filter as well. Any of the Purolator line, or it's clones
(Motorcraft, Proline, Powerflo etc.), or WIX/Napa Gold/Carquest Blue. I find that the Napa Gold seems to help with the startup rattle that these engines have. Currently I'm running a Motorcraft FL-910 on both of these trucks. Oh, and I run them at a 3k interval. Before some of you will slam me on this you all know my position, after working at the dealership and seeing all the sludge on engines with 5-7k on dino. So my policy is typically 3k dino, 5k syn. That being said, this engine has no sludge issues at all, and the 2 that I maintain don't get much mileage. It takes 6 months for grandpa to go 3k, and it takes the camper a year or more to go 3k.
Please let us know what you decide,
Justin