450-366

Just for starters, bushes to fill in the excess between the existing rim cut and the new, making extractors/ejectors. Sight blocks. and many other things.
Some are better done on a mill, but if one hasen't access to a lathe, then one must presume a mill is also unavailible.
I supose that it could be done with very carefull planning and pre-measurment, however it leaves no margin for adjustments.
A good lathe should really be the pre-requisit of even a well equiped amateur machine shop.

Regards