Hey Grant,sorry about the engine. If the full flow oiling is not an issue to you, any year 261 should be fine.I remember the early 261 has a different style of main bearing shell locating tang.I think it was changed around 1955.63 4x4's used the 261 in its last appearance. The later style main bearings are slightly less expensive.Check you blocks out carefully around the cylinder bores. I have seen a few with cracks running vertically on the thrust face of the cylinders. Have the rods resized, the ones on both my 261's were not done right from the factory.Balancing is a good idea.Inline six cylinder cranks are balanced seperately from the rods and pistons.If possible, try to deal directly with the man who balances the engine,less chance for a problem.If using stock style pistons, you may want to check the deck height carefully. Replacement pistons fall as much as .040 below the block deck.Try to keep the pistons no more than 20 thou below the the deck, heps promote turbulence and a faster burn.Running mild cams, I had absolutely no intake to piston clearance problem with .040 cut off the block deck, but check it for sure.We gonna line up the 261's at Wendall for a race of honor? lol
