I have some experience in this area, to date now I've down around 5 full playfield swaps (DMD & 1 SS).
Firstly, if the Addams playfield was purchased locally it is most likely a 2nd (or 3rd). In good light, make sure the clear is even and has not got 'waves' in it. You don't want to do all the work then have to restart over. If the clear is not up to scratch, then HRP (El_Timbo) is the man to contact.
You will be able to reuse most things and no point in buying new brackets etc unless they are stuffed. You will need the following:
- New pop bumper lamp sockets. I would recommend replacing ALL pop bumper components (playfield topside) ie skirt, base, spring etc as well as coil sleeve
- New screws for pop bumper brackets (the ones which go through the playfield to secure the bracket)
- New coil sleeves for each and every coil.
- Flipper kits & bushings are a must
- I would suggest new plastic posts. They are cheap enough to replace esp for a new playfield
- Check your metal kickouts - most likely these will need repair (TIG welding)
- As far as all the underside mechs - fully strip, degrease, clean and rebuild (with coil sleeves) and test each coil as you go
- New nylock nuts (cheap)
- Boards - worth rebuilding whilst the game is in rebuild mode
- New T-nuts
Take lots of photos before and as you progress. Its very important to keep an eye on the hex screws you take out. If you put the wrong size in (ie for a #44 globe holder) you'll go straight through your new playfield).
I recommend to separate the looms as you go. Ie take the solenoid loom off, then switches finally G.I and controlled lamps. Work in reverse order when re-assembling.
I find it easiest to work on the playfield out of the machine. I designed, built and copyrighted the following playfield stand
http://aussiepinball.com/index.php?topic=67.0 
Only kidding Nino is actually the inventor I just built one and use it for every machine I rebuild. For about $50.00 in materials I find it perfect and much easier than the rotisserie type.
I'm sure you're all over cleaning the other things like ramps, plastics etc. I also go over the lamp boards (under playfield ones), reflow the header pins and give them a good wash as well.
I'm sure there is stuff I've forgotten....
Greg from RTBB is the man to contact if you haven't already for the parts. Best prices and service.
