Guys, progress at last on two fronts (out of three)...

Checked TPS, it was reading very close to 0V, so adjusted back up to 0.23, idle is now 900rpm when warm

Drove the car today, and she was still mis-firing + the base idle is set too low (approx 500rpm with ISCV disconnected), so I thought I'd adjust the idle.

While doing it, and with the engine running, I could hear the amal valve clicking on and off at random, so I wiggled the wires and it clicked even more...

Had a spare which is now on the car, cross fingers that might be my misfiring sorted too

Only thing is, my base idle screw is stuck, it won't budge