I ordered a third brake light. They sent me a poorly made aluminum stalk and a light with two wires and a connector to put on the wire. The wires coming out of the lamp are a red and white. I will be putting this to the third light brake connector. My question, are these led lights polarity sensitive? If so, how do I know which wire connects to what? There is no wiring diagram, no instructions and I am at a loss on this. Any advice would be greatly appreciated

Yes they are polarity sensitive, red is positive though. Its been suggested you may have to extend the new light cables before they will reach the existing normally redundant third brake light socket located forward of the fuel tank sensor. The wiring schematic shows just 150mm of free cable after this connector exits the main rear loom. Its the one with green/purple +ve and black -ve wires. The connector is a two way Econoseal, hopefully loose pins and male part of connector were supplied otherwise you will have to order one which comes as a kit of individual parts.

Thank you for your help, I sure am glad I found this forum. Thank you

While on the topic of wiring, has anyone done the SPA oil pressure / temp gauge? I'm looking for a recommendation for the best switchable power to wire the gauge. Thx

I fitted an SPA dual Oil Pressure/Oil Temperature gauge to my M3W back at the end of 2014. I did do some posts on it then but the pictures are no longer retrievable.
Unfortunatley I have now sold the car so I am not able to show a picture of where I picked up the power from.
It should obviously be continually live whilst the ignition is turned on and there is a fairly thick wire (which from memory was yellow) coming from the ignition swicth and I connected the power feed (Red?) cable from the guage to this cable using one of the Insulation Displacement type 3M cable connectors. The gauge draws very little current so this is more than adaquate.
The sensors for the gauge are mounted in an aluminium billet sandwich plate that mounts between the oil filter and the engine.
You will also need the threaded adaptor that holds the sandwich plate in position and allows the oil filter to be screwed on up against the sandwich plate.
The gauge, sandwich plate and threaded adaptor are all available from Merlin Motorsport (at Castle Coombe) in the UK

I found this set up particularly usefull because you get a real-time reading of exactly what the oil is doing with regard to temperature and pressure..
Good luk with your installation

There is an article about installing the SPA oil pressure and temperature gauge on the Morgan Three Wheeler Club website 5 Speeder pages, linked article May 2020 Bulletin. These are available to members only. If you are not a club member PM me and I will try and sort a copy out for you. I don't remember the power supply being a problem, just an ignition load supply. I think that I may have used the heated seat supply fuse, as I don't have that option on my car. As KBMOG says, it is a good and useful gauge and fits in well with the other instruments, unless you have a Heritage dash.

KBMOG & Planenut, thanks for the information. I did get the parts from Merlin and also have the article from MTWC. I think I've got everything sorted now, thanks for the advice. Now just need to figure out the best location for the gauge as I do have the Heritage dash. I'm likely going to create an enclosure for the gauge in the center behind the ECU. I'll post some pics if my upholstery skills prove worthy. Thanks again. Cheers.

Thank you all for the help, gauge installed successfully. (Yes, no oil pressure as engine is empty from install)
https://www.tm-img.com/images/2021/03/02/download.png

Looks pretty cool! Can we get a better picture/more details, please?