86' 300E Climate Control out of Control

My Climate conrtrol has been getting progressivly worse, if it's on the Off or Economy mode the A/C compressor keeps swiching on unless you hold the Off or Econo buttons down with your finger, so I beleave the problems a bad or coroded contacts at the switch. Can the box be taken apart? contacs cleaned? sort of like the seat adjustment switchs. I know that the rebuilders say "if you open it we don't want it". Or should I just go for the rebuilt unit? Thanks in Advance, Chris C.