I have my Newmans perma-taped on the inside/outside. I cut down my scoop coater to run just inside the tape. Once the emulsion is dry I might card over the gap with more emulsion, or I just apply some 1" masking tape on press.
I block out all the reg marks with emulsion and post-expose.
Thing I learned awhile back with water base and especially discharge, if you try to tape off reg marks the ink moisture will build up and seep out from under the tape, and with discharge that means phantom lines burned into the shirt. It can even leach through the emulsion where there is no reg mark. (you can tell it's leaching through if the emulsion is tacky underneath)
Blocking out the reg marks altogether and leaving the screen un-taped solves everything.