When I have to do the lim gaskets I will block the tb coolant loop in the lim with npt plugs, and open up the coolant bypass, also in the lim unsder a flange bolted in with 2 bolts, I believe under the egr connection.
I got a spare s/c to test out porting it myself, and all bearins seem fine for now. Just replace the coupler if it is going bad, and port the outlet at the same time if you want to.
I built a template and used a router with a carbide bit for the outlet shape. The inlet I opened up to 76mm using 2 bits, one to step in ~2mm, another to remove this remaining step and a flapp 80 grit sanding drum to smooth the lip that was left at the bottom.
