Hello, I was going some research on adding a 406 ELT to my 1990 J.  I saw there was a service bulletin for this.  My antenna is internal, and I’d like to keep it that way. When I asked about the availability from a service center of the SB, i was told it was no longer available.  My question is, have you added a 406 ELT to your plan e, and kept the antenna internal WITHOUT using the kit called out for in the service bulletin?  im at a loss at what to do ELT wise.    thank you