Now for a slightly longer answer
Years ago a book was written: "How to keep your Volkswagen Alive-- Step-by-Step Procedures for the Compleat Idiot" In "plain english" explained just about everything one needed to know in order to keep their air-cooled Volkswagen vehicle properly maintained, to and including engine overhaul.
Also explained which parts of the vehicle would need to be attended to by a properly equipped shop, as the tools and training needed to perform certain tasks was not economically available to a typical vehicle owner.
SO... Does such information exist for the pipe organ? I imagine it is "out there" but not conveniently
Could reasonably skilled tradesmen within a church congregation take care of the necessary preventive maintenance and extend the "mean time between failure" of their instrument or would this be too much to ask? I am thinking about stuff like keeping the wind system in good order, lubricating blower motor bearings if so equipped, making sure the wildlife doesn't befoul or consume the mechanical and electrical devices, cleaning, etc...
Just HAD to throw that bit of fat into the fire...
Now... My definition of a "Restoration" lies in the root "Restore"... That is, make the instrument function as it did when new. If what I suggested above took place, shouldn't be too much of a job
for the local organ builder to remove pipes, open windchests, renew pallet leather and felts, etc...
clean internal components not otherwise accessible during preventive maintenance, reassemble and tune. May require attention to wind delivery/regulation, but that should largely be accomplished in the proactive/preventive maintenance program "within the organization" unless special, custom parts need to be procured.
Anything "beyond" that could be classified as alteration, expansion, modernization.
Modernization could include the upgrading of electrical components to devices more available/serviceable, adding of electronic combination action, but would NOT include conversion from mechanical key action to electrical, etc... I would firmly classify that as an ALTERATION, as "tracker action" allows for some measure of control of how the pipe speaks by the organist, whereas an "electrical" action sufficient to accomplish this would be an extremely expensive affair indeed
Look at the prices on servo controls for radio-controlled stuff, you will plainly see what I mean!
So there it is... A starting point from which I hope much discussion ensues.
Can of worms open, flame suit on