On your deal, especially if you drive it when the outside air temps are below 50F, I would use either 5W20WT, 5W30Wt or 10W30 WT.
As far as which brand I like and use Valvoline oil based non synthetics oils, maybe VR1 with higher valve spring pressure for solid roller cams up


Mr.Cab Racing and winning with Mopars since 1964. (Old F--t, Huh)