Unless I'm way off base, the REAL wood in these cars is coated with a poly-something finish anyway - it's not 'bare' wood like a dining room table or something. So you really want something that will clean the grime off the 'plastic', if I may call it that, and then apply a bit of protective gloss/shield. I've found that any good all around cleaner APC like Simple Green or whatnot is good for cleaning, and then I coat the "wood" in my Eldo with Duragloss Aquawax. But any halfway decent protective coating should do - just remember you're not waxing bare wood.
I know this is not bare wood, but the wood is treated very similarly to most furniture. I was just wondering because the wood in my old '88 FWD Fleetwood was real wood without any plastic coating so I had to use Murphy's Oil Soap to clean it.