Help me identify this Ford engine for a customer...

It’s an FE series engine. Displacement is on you. Could be anything from (IIRC) 360 inches to 428 inches.

Edit: it is a non adjustable valve train so you bolt it down.

If it’s never been apart for hard seats, you can expect at a minimum the exhaust seats will be pounded out and most likely, unless you are very lucky they will have several cracks.