@MED posted:While @gunrunnerjohn didn't write this, he may have done this as I had done in places around my layout. As I installed the gargraves track and thought it would be a place for a future isolated rail, I used insulator pins to isolate one of the outer rails, then after track was installed, did as John wrote to jumper the isolated rail to grounded rail under the table to allow for easy isolation in the future.
I didn't install any insulators, I have a Dremel tool. If I decide to have insulated rail signals, I'll just add a gap were needed. I am thinking I'll use my ultrasonic sensors for the job anyway.