Sprayed the plastic backs of my driving lamps with the special paint for plastic without any problems, cellulose will chip off as it's not for plastic.
The actuator will operate when you press the fob button if it has power unless it's jamed, undo the actuators mouting screws and disconnect the linking rod to isolate the actuator from the lock then the try the door pin if it still doesn't move your problem is in the lock area the drivers door should lock/unlock normally with just the door key.
Anyway what model of disco are we talking about? as with a D2 the actuators are in the lock.
Cruise control ECUs are reliable there's never any issues with them, although there will always be one.
Are you sure there's a problem with the ECU normally it's splits in the rubber vacuum hose that gives a problem.
Duck Tape. Yup I have a roll of the genuine stuff on my garage shelf must be 40 or 50 years old, it has the consistancy of thick grease on a hessian backing it's very sticky and waterproof, it was used for a temp to permanant seal to underground telephone cable joints in the good old days.
I've never found a use for it but have used Duct tape or is that Gaffer tape
It just that the servo part can gets 'gum up' therefore won't operate to its full extent, just unplug and unscrew taking care of the fibre washed, spray and put back just a five min job. You could also try a whole bottle of injection cleaner in your fuel.
Check the idle control valve (stepper motor) at the rear o/s of the plenum chamber remove clean with brake cleaner and replace, also check the vac/breather hoses for leaks.
The heater matrix is always hot and the air blending flaps control the temperature from the heater vents, therefore the flaps are not operating when the controls are turned, usually the control cable has come adrift although unusual for both controls not to work.
You will only have a hole if you have a timing belt and or a clutch, the theory is any oil escaping via a faulty seal will drain out and not contaminate belt or clutch plates, also the holes are positioned at the lowest point of the timing case or bell housing.. But then you know all that.
Only two reasons for sunroofs to leak and both are seals, the so called drains are only there to take water 'run off' should there be water laying on top of the glass when the sunroof is opened, thats why they are only at the front of the sunroof.
Is it a sender or a switch, it's a thermostactic switch that via contacts illuminates a dash light when a preset temp has been reached therefore has sent this information to the driver. Haven't a clue what the preset temp is.
Most oil companies have a search facility Castrol does here in the UK.
http://www.castrol.com/castrol/iframe.do?categoryId=9024084&contentId=7044829
I have a D3 service schedule as a pdf file I can send it if you PM me with your email address.
The heater motor/fan unit can be seen from the passenger footwell just undo and release, it's the 200 series that requires some of the dash out to replace. Even the heater matrix can now be replaced without removing the dash it can be seen to the left of the fuse box area at the back takes an hour although pipes have to be cut I believe.