beagle_senior
Josh, ill need a hand if you know anything about wiring???

do you have a factory wiring diagram for the gauge/sensor? 

ok with the help of josh MRTurbo, have sorted out the coolant temp gauge.
 
It was a simple matter of no earth from the engine bay compartment fuse box to an actual ground...

walks off to check fuse box earth...  What colour was your earth in the fuse box?

it was a white wire with a black leader, the IE1 junction is the kick panel on passenger side, the EA3 junction is the big white plugs in the engine bay compartment fuse box. the white and black wire is meant to go to the 3rd pin where the line is, then go to a ground
 
 

 

You will likely have the same problem Kris. When I built my loom I started with the original loom and cut away everything unecessary from it.  I kept all the sensor wiring that ran through to the body loom, one of these was the ground. 

You need to make sure the ground is connected somewhere too, they used to attach to the back of the intake manifold originally.  I would assume you have it connected at that end though as from memory the starter relay misbehaves with it disconnected.  Though maybe you sourced that ground from somewhere else?
 

yeah because I have moved the fuse box into the boot, I just made a new earth for it in the boot

I'll need to have a dig around to see whats going on.  Has been to long for me to remember off the top of my head.  I do not however remember earthing anything from around the fusebox area.  Thanks for the tip Alex.

no worries mate, best of luck with it, hope its an easy fix for you...
 
On another problem I have found, I have a hairline fracture/crack in the sump/pan around the flange. I have the alloy moroso sump on now, and I can not find a mobile welder that will do it for me. As I dont plan on taking the sump off...
 
Is there another option that I can persue??

If you don't plan on taking it off intend on it leaking.  If its leaking at the moment, you won't be able to weld it (well at least not without it still leaking).  Aluminium is fussy at the best of times when it comes to welding.