Don't do it there is too much chance of it eventually diss lodging during future service and getting into the engine.
I have done plenty of heads where I've broken into the bottom 1/16th of the injector ports and had no problems with oring sealing.

that is of course unless you're missing the O-ring retaining discs on the OEM l67 injectors.... thankfully almost every aftermarket injector has a metal O ring retainer Groove