Update from the results of the weekend.
As above - powertrain is back in, the brake servo is also back in, after the wiring went in. Driveshafts, exhaust etc are all hooked up, ready to go. The radiator has either rotted out, or been tapped on one end and is now leaking, which is a pain, but less painful than I was expecting to get a new one from ECP.
Anyone got any thoughts on the longevity of the clutch master cylinder - we ran through about half a litre of fluid and there were still the occasional bubbles coming through. Hopefully a few days with fluid in it again might just tighten up any loose seals (or they'll start to leak).
Then we got on to the nasty stuff: making sure all of the things worked before the dash went back in.
Central locking wasn't working, so I checked the pump on the red Golf - worked fine. Chuff suggested fitting the flasher relay back, which I did - hey presto - the central locking works again. Go figure.
Next up was the fuel gauge - not working - we tried the two instrument packs and no joy. DannyP called and suggested we tried another sender - Dave's tank was still on the floor, so although it has a different connector we jerry-rigged up some wires and shoved them into the fuel sender connector on the Corrado - working fuel gauge! I'll have to see whether taking it out and making the fuel slosh about brings it back to life, before taking the top of the tank off to investigate.
During this Chuff noticed the temp gauge had popped up to 80Deg C. This issue was resolved by removing another relay I'd fitted during the central locking issue resolution.
Then things got even nastier - the ABS light was on. When I got the car the ABS was unplugged/not working/light had been disconnected (I forget which), but I'd had the pump on the bench and checked for the telltale *click* so we were hoping that was OK. Next up was to run through the wheel sensors. The connectors for the rear ones are under the rear seat, in case you're wondering. All of these had a resistance except the front off-side, which read open. After some scratching around I found a random sensor that had wound up hanging up with the crank position sensors and lambdas on a wall in the workshop. It had the same plug and gave the same resistance value, so I plugged it in. The ABS light was still on. We disconnected the battery and came back a few minutes later and tried it; it was still on. We disconnected the battery and moved the sensor away from the alternator pulley it had been sitting on; it was still on. We tried starting the engine, in case it needed to see 'all systems normal' to switch off. Nope. We were about to start packing up for the day, when I spotted I'd left the NS front sensor disconnected.
DOH!
ABS light out.
I think all systems are now sorted and happy.
As we'd made progress we then got the dash fitted in and started routing the wiring which went well, but by that time it was time for Chuff to head for the boat and me to head home for dinner.
Many thanks to Chuff and DannyP for the assistance - new rad and an ABS sensor and we could well see this being driven in a couple of weeks.