Cleaning prep for painting...

Was there a hurricane in Groton,CT that I missed

I would use dish soap and warm water. I also scrub a bit with an old toothbrush.

What about the delicate parts like PE, and the fact that the pit is still open?  Won't that make it a little difficult?

(the hurricane was Katrina, and I (aka TJ ace) was living on the MS coast at the time)

Yup soap and water will do the trick, I also use Polly Scale's Plastic Prep, that also works very well.

Then try a q-tip with soap and warm water. Be patient. You have to be gentle, so it might take some time.

How about taking an airbrush and spraying soapy water or a mild cleaning solution at higher pressure... sort of like a mini pressure washer.  Hmmmm... I got an old model with a few years of dust on it... think I will try that out myself.

70% rubbing alchohol on a soft cloth. wipe it and it drys quickly with no residue