Well after 5 and a half years I finally got of my lazy arse and fixed this.
After disconnecting the battery I removed the two bolts that hold the airbag/horn assembly to the steering wheel.
It was then pretty easy to remove the gear switches with wiring harness.
Pretty easy to pry open the switch assembly to reveal the small circuit board.
The switches are operated by a couple of micro switches.
With having better access I thought I'd try to clean with contact cleaner again and blow it out with compressed air but this didn't fix it.
Bought a couple of 4 pole micro switches (only 95 cents each), soldered them into place and it changes gears beautifully now. Should have done it ages ago lol
These are the switches I ended up using (the 3.5 mm ones)