[tommr]

Actually my daily driver 86 Monte with a 4.3l FI turned 400k a few weeks ago. valve guide seals and head gaskets is all the motor has seen. Heads had no machine work. Have seen several 350s with nearly 500k--ex police and taxi with tons of idle hours. None of these are pushing 20k lbs down the road like the 401 does though. Ditto though on the parts availability issue. Allison transmission in the bus modernizes that aspect. Next is front axle and suspension conversion to modern axle with air disc brakes and air beam suspension--hopefully this winter. Have to upgrade engine/rear axle/rear suspension at the same time to get all the mount and driveshaft angles worked out. Bus is loaded with 50 and 70 year old components for which very little or no replacement parts exist.