Morning Graham; two methods of attack here - if you can't undo the cables in behind them undo the black knobs (there's a pushbutton on the side, press it in and whilst pressing pull the knob off) then by unscrewing the silver bezel you can push the cable back through the dash. This might be easier for the choke and heater valve cables. The other cable might be one piece with a nut in behind, so if you look in the footwell by the steering column you'll see the large flap control that directs heat, just above the gearbox tunnel, and you can undo the short cable down there then remove it with the dash.
The wooden dash fascia is screwed to the back surround and the heads of the screws are easily found, but the gauges can be either screwed / clamped just to the wood or else to the backing surround - I've seen both over the years depending on whether they've been disturbed before or not. Some of them also have a metal 'rim' which acts as a strengthener in behind and against which the long clamps are tightened. If it was me, I'd remove both gauges before removing the dash, it makes it lighter and less easy to bend or crack when moved.