DO NOT USE WD- 40 near any wiring , it brakes down wiring insulation and causes it to swell, silicone is much better

I have had good luck with ppg acryliclean. It is a mild wax and grease remover. Before i apply it i make sure all the heavy build up is removed by wiping motors down with a rag. After that i just simply fill up my hvlp gun and spray away! I use this same method every time i complete any work on a concours quality restoration also. Never hurts to hit the shiny spots with some good chrome polish after you've acrylicleaned the whole compartment.

Simple grean (spray on)
Hit the bad areas with a 100% cotton rag
Spray off Simple Green
Dry with 100% cotton towel

You don't need anything harsh.

CRC 656 is way better then wd40, stronger and safe.

Steam clean

Do Not Use Castrol Purple Stuff

a few drops of dawn in a spray bottle, use running water to rinse. no jet stream. only use simple green on the bilge as it does have caustic soda in it, then blow the engines off with air.

Dont let the Dawn soap get on paint as it will strip wax, you wont be able to see it but it will. you can actually use a stronger version of the dawn and it will cut grease, get the orange scent as well as it has fruit acids to help. use a very soft sponge or shmmy.

Ummmmm , silicone will swell seals. Since it swells rubber I'd think many plastics would be affected.

Thanks for all the good tips guys........ I think I will keep it simple with the Dawn and the Simple Green for the bilge......

Soap, hose, dry and then CRC. CRC 656 is AWESOME stuff for protecing metal parts.... I had started with wd 40 then was turned onto CRC and swear by it.. I buy it by the gallon at Boaters world and use a simple 16 oz spray bottle to apply it....