New barrel question

[Scout]

Noobie question:
If I rebarrel my Lyman GPR to convert to flint, is the touchhole predrilled in the barrel or does it have to be drilled to match the lineup with the lock?

[D. Taylor Sapergia]

A Lyman replacement barrel, ie:  a drop in barrel, will have the vent installed.  It may or may not line up perfectly with the pan.

[Scout]

A Lyman replacement barrel, ie:  a drop in barrel, will have the vent installed.  It may or may not line up perfectly with the pan.

Thank you, I was told that in another post too. My question is does a Green Mountain etc. barrel come with the vent drilled and liner?