the pad number likely means it's been rebuilt [or might be a CDN number code], the block casting number is all you know except if it has the side mount bosses cast on the block it's not a 57, that started in 58 .... and don't count on the 220HP, that depends on other things .... that block is the best [58-66] IMO

Bill


Moved over to the Passing Lane

"When we tug a single thing in nature, we find it attached to the rest of the world" ~ John Muir
"When we tug a single thing on an old truck, we find it falls off" ~ me
Some TF series details & TF heater pics