Check the control cables in the engine bay, spray the ends where the cables go into the sheath with loads of wd40 and then oil/lubricate. Do the same with the spindle on the heater matrix box.
It "should" be in the square hole on a bracket in front of the cubby box.
Bracket looks like this
If it isn't someone has moved it, remove the cubby box and check under the metal panel.
Mostly miserable farmers round my way so not many responses, do get a wave every morning from a nice looking Series 3 going through Melksham/Shaw.
I'm not saying all farmers are miserable, just the majority round my way.