It's alive! Fitted the part and all working, just used multi purpose in the end.
Wasn't as easy as it should've been though. Checked the sensor and was working fine, because of the little rub through on the "new" sensor wire I opted to cut the wire at the top heat shrink where it had rubbed and then resolder at the top. This was all a piece of cake.
Greased everything and pushing the axle through and it just wouldn't go in, checked and the axle wouldn't fit through the sensor which is odd but hey ho. So I ended up using the dremel to sand the inside collar of the sensor just enough to get the axle through. Just took it for a test and all is good
my plan was to change the oil and filter today too but that'll have to wait until tomorrow now.
When I had a look at the old sensor the only thing I could see was down the bottom where the wire attached to the sensor the wire insulation had pulled up and away exposing the wires (not bare wires) and I guess moisture got in there and focced it up. It started with the speedo giving odd readings, reacting to other electrics like indicators and then just died. Just thought I'd recap incase anyone has a similar problem.
Thanks again to all you guys on here helpin me source a part and advice along the way