Not sure about what oil to run after a rebuild, but I run 15W40 Rotella in my 1959 W/ the 235. But it probably has over 100K miles
I also run 15w40 in my 1991 Jeep Wagoneer V8 with 129k miles, so I get adequate oil pressure. In a basically brand new motor, wouldn't you just run 10w30?
