If one was to remove the drivers and tweeters, paint the cab and re-install them, what are the
chances that the re-install will not be correct? Is the driver installation just a simple screw-it-all-in or is there more to it?
I assume the drivers need to be removed even for wallpapering.
I'd suggest removing the drivers for any work on the cabinet, esp
if you get some workman to do the job (and not DIY it), lest there
is any accidental damage to the cone or surround.
The reinstall should be fine, if you follow the usual precautions.
After removing the screws, take a picture of all connections, or note the wire colours - the drivers
terminals will have +/- marks. Also, label each wire with some adhesive tape so you will not reconnect wrongly.
Also, once the drivers are removed, use plastic sheet and paper to cover the insides and the hole, so
the paint and dust will not get in.
Usually, the drivers will be just fixed with screws, but as Anthony said,
there will be a sealant or gasket. You can either get speaker gasket
tape, or cut one yourself out of a sheet of closed cell foam (from local
upholstery shops or even the packing material from a LCD TV or monitor)
and use rubber adhesive.
Only possibility of damage is if your cabinet is made
with MDF, which does not take kindly to removing and refitting
the screws - the threads may get stripped.
If you run into that, you may have to glue a matchstick
into the stripped hole with fevicol and let it dry, before fitting the
driver back.