[Having trouble removing sump plug.]

That one looks pretty bad but it will still shift, clean off the visible threads with a wire brush first & if you haven't got access to a proper plug remover attach a big set of mole grips across the best looking flats that still allow you to apply force. Then first try to tighten the plug, I know that sounds counter intuitive but the very slightest of movement is all you need & it will then unscrew. Many moons ago I picked up a purpose made spanner that has never let me down .....probably fatal last words!

 

[Oil Warning Light - for the 4-cylinder engine ?]

Pete, I fit something very similar to my TR4 engines, I fit it for convenience in place of the foremost oil gallery plug as per the attached phots. I use a generic 20psi switch on a simple thread adaptor that a friend turns for me on his lathe & I then zinc plate them. Orange warning light on dash.

John B

 

[Cut from TR4-6 door]

Found it...this is what I've got, it's pretty rusty on one end but no use to me so you can have it for the postage if it's likely to be of any use for you.

[Cut from TR4-6 door]

Pretty sure I've got a top section like that from a TR4 that I lent to a friend a couple of years back to use to make moulds for fiberglass door cappings, I'll take a look later & let you know.

Regards

John