If you're willing to ream out dye titanium and replace the bore with some ****ty SP aluminum sleeves you never deserved the sparks.
Curious why you think the bore size is a problem to begin with. It's more or less proven at this point that you aren't going to make the paint shoot any straighter messing with inserts, and if you are shooting a cocker or pump there are 3d printed detent inserts that work fantastic