6 4Runners now my 1st Landcruiser, 2002, fully loaded, friend of mine owned since new, picked it up yesterday. What are my options with the nav/headunit/climate control system? Bad/hard to read screen that says "CD not detected" and a volume control knob that seems to say "FU" to any input.... Any "must do" mods that I should do? New "stock" tires and a new AC compressor/dryer just completed.