Using this engine would be a really smart move. I'm a couple of years younger than your father and can still do a lot of this work, but I'm getting really slow at it.
Could not do it for $11,500.
Purchased an L88 in the early eighties from GM for a boat we were working on. Decided to take it apart to check everything. Found an extra rod bolt in the pan along with the Detroit News. I think the date on the paper was pretty close to when they assembled the motor.