Any Old School Machinists Here?

Wait or find someone with an automotive line boring machine, preferably a newer machine. This is something you don’t want to mess up. Nothing against your friend, but I ran a boring bar for 30 years. You need special tooling, like a boring tool that has support at the opposite end of the spindle. A big boring tool with a diameter of 2inches that sticks out 2 feet on a horizontal boring machine will sag due to gravity if its not supported on the opposite end of the spindle. Its not that it can’t be done, but the time involved would be stupid and nerve racking. Thats why line line bores are purposely designed specialty machines.

And yes I would have it align honed for size accuracy.

I would let an automotive machinist with less than 10 years experience touch my engine.