I bought one that was rebuilt buy P.O. He also ran it about 10 minutes and it stoped. He had 1300 into it but did not know in 54 the mains were SHIMED. I got a new oil pump, cam, lifters, fuil pump,clutch and a rebuid head for 150 frog skins. If it has been run, good if not make for sure it has been shimed on the main bearings, If not, it could ruin the block crank and you could have some nice parts for a good block. F.Y I. I rebuilt one in the 80s and it was a piece O cake. After 500 miles I drove it from Wa. to Ca. no problems other than the wife. It's a dog on good motor.