Any Old School Machinists Here?

Have a big block 440 looking to get built but I am installing after market main caps, main cap studs and girdle. I need an align bore and hone done. Local machine shop said they r 8 months behind. Friend with a boring bar that has bored cylinder walls for me in the past said he could do it with a boring bar.

I've never heard of using a boring bar for main caps? If this can be done would the mains need honed after bored? Is there any advantage to wait and have it done by a professional machine? Didn't want to wait 8 months but maybe boring bar for main caps is something that has been done for years and I'm just not aware of it