What are you fellows using for your electrical sensors, and sending units?

For years I simply used teflon tape as a thread sealent, but it seems that this may not be the way to go with the modern single wire sensors, and sending units, where a good ground is required. I am installing new electric gauges, that come with specific senders, so out come the old, and in with the new.

Would teflon "paste" work, or is there something specific I should use?

Thanks Bill