Papa -
There's lots of good advice and help on this site. I suggest you read the Pinwiki manuals on system 11, and the general cleaning guides. If you have never tinkered with a pinball machine before, you can make things worse by doing something you shouldn't. (That's why there's lots of advice and guidance here - we learned from our mistakes and wanted to share them.)
Get some cheap parts - coil sleeves, 91% or higher alcohol, Q tips, Novus, rags (I use old t shirts - less lint, cheap, watch out for seams and iron on decals), a good light, decent screwdrivers and other tools, etc. There are lots of suppliers out there - we all have our favorites,review the site for opinions.
There's also a lot of parts information on line - Marco and others post the parts book pages so you can have a better idea of what you need.
Report back - we're always curious about how the repairs/fixes are going.