red rocker switch & service manual

I recently obtained a '72 MGB that came with a house that I purchased. I don't know which needs more work, but they both have potential. Although the car is the lower priority, while pushing it into it's new garage for the upcomming winter, I noticed a transparent red rocker switch on the left side of the dash that looks as though it is from the factory. It is not for the flashers and I haven't been able to determine what it controls. Any ideas would be appreciated. Also, who makes the best service manual to purchase. Although the '72 had minimal emission equipment, I noticed a few lines plugged or teminated. Who's manual would detail the routing of hoses under the hood, or should I say "Bonnet"? Thanks.

as far as the books, i suggest BENTLY

http://www.rb.com/mg/x115/x115.htm
ISBN 0-8376-0115-0

i would suggest calling your local book store and give them the ISBN number, and see what thier prices are as compared to AMAZON, MOSS, etc.. it also can ordered directly thru BENTLY themselves..

i called my local store and they actually beat the price that everyone else was asking for it...

good luck..

Hal...
have the same switch on my dash but have no idea! If you find out please let me know! I also think that it is factory but where does it go or what to?? I was extremly careful removing it so as not to break it and have not been able to trace where the wires go yet!
Mine is a 72 MGB GT??? If that helps?
I'll keep looking also!

that is your brake warning light. it comes on if it sences low preasure on the brake lines. the switch part is to test the light. if you push it and it lights, then your warning system works. I have only seen one that worked ever.(mine) the insides corode with age and lack of use. the plastic degrades over time and the switch cracks. and the bulb inside is unavilable.with some creativeness however, you can take it apart and make it work.

Good show on that last line Gavin. That goes for a whole lot of things on LBCs if you have plenty of patients.