How do you remove the sender unit from the tank?
Got the wires and lines detached, the workshop manual I have doesn't even mention how. Just how to remove the entire tank from the car.

For under car tank, rotate plate (that has lines attached) anti clockwise with a dolly & hammer.
If you look closely it 'screws' in - not with threads, but a sliding compression action, if that makes any sense.
You will need a new gasket I'd think.
Cheers

When you find somewhere to get new tank gaskets, please let us all know where.

Flighter
When you find somewhere to get new tank gaskets, please let us all know where.

Me to, I looked everywhere for the square O ring gasget and had to use a used one.

retro666

Flighter
When you find somewhere to get new tank gaskets, please let us all know where.

Me to, I looked everywhere for the square O ring gasget and had to use a used one.

I just found a couple in amongst all of my spares sitting in a packet.
 
But sadly the RS is a no go, it's developed some sort of issue and will not fire. So it's gone to my mechanic for a new engine (Was gonna happen and will be a high performance engine ;) )
 
But cheers for all of your help on here.

This reminds me of when my old man picked up a MK1 Escort with intentions of fixing it up but sat in the paddock for about 20 odd years. I found it sitting there as a kid and took interest in it so he gave it to me as a project of my own. The tank didn't hold fuel so I ran a hose to a jerry which sat in the passengers side, threw some petrol down the carby and off she went. Might have been running like a dog but I still spent days doing burnouts in it and still hasn't died on me yet. Lucky I guess.