I've been in your shoes but with a Hayabusa engine (when I was young) I spent 5 hours one way and then spent two nights in a hotel because I damn sure wasn't going away! Your 4 hour trip was worth every minute you spent and it told you almost everything you need to know. If you don't have red flags waving in front of your eyes you never will. I would suggest you get on the phone tell the builder you want to schedule 30 minutes of his time ( and not 4 weeks down the road make the appointment with him for the next week) and want to see and discuss progress of your engines, take pictures of your engines and parts and discuss a delivery deadline. If you have a boat and the money to rebuild engines then your old enough to smell bull**** so be prepared.

If you delivered the engines I would be prepared to take them from his shop the day you show up, take your, truck. engine stands, straps, pallets, boxes whatever you need to take ALL your stuff back home. I took my engine from the builder and blew a whole season of racing it was worth every minute.

Best wishes

Mine has been at machine shop prison for 8 months. Hard to get calls back. Last time I was told it is almost ready for the dyno.
Hopefully it will be done soon.

The icing on the cake is when you get the call to bring some part you dropped off with the blocks six months ago.