There’s plenty of room to widen the holes to accept the inserts.
I used these…
Specifically the 440 press inserts. (And in another ‘oops’, installed them upside down according to the diagram on this page. I’m lucky I got away with this. Its really not that difficult.
There’s also these, made specifically for wood…
My black anodized steel bolts arrive Friday and I’ll lube and install them then.
I think I’ll cut my losses and leave the corner bolt off until I get it into the hands of a good woodworker who can repair and install for me.
I still would like to see this incorporated into the rumored new instrument (if Guido’s hints bear fruit.)