[TR] TR3 Cigarette Lighter Install

[Ed Oot]

Folks,
The desire is to install an auxillary power source in TR3 to power a GPS. I
have searched the archives and read everything I could find, but still have a
couple of questions.

The car is still positive ground. The adaptor I picked up from Wally World is
two wire, with pos to to the center. Given the fact that it is two wire, is
there still a concern with grounding through the case/bracket? Ia m assuming
that I keep the polarity the same and ground the positive.

In one post Randall suggests tapping into the brown/white side of the ammeter.
I assume I would tie into that with the negative lead from the socket and then
find a good spot to ground the positive lead. Given that, again, is there
concern with the mounting? He also mentioned the need for a fuse. How do I
determine a good size.

Thanks
Ed