Denny; I used a plastic garbage can to see how well this was gonna work.I was so pleased with the results that I decided to go to a larger container.??????? There was a farm sale down the road from me and I saw a larhe tank in the line up of things for sale,(the type that slide into a pickup truck bed)the top of the tank was damaged,it didn't sell.The auctioner told me I could have it for hauling it away.
When I got it home I took a saws all,cut the top out and placed four pieces of old three eighths boiler plate,equal distances around the inside perimeter,connected them all with wire,threw in to two large boxes of baking soda,filled(water)to about six inches from the top. Hook the battery charger(+) to the plates, I lay a two by four across the top of the tank and hang the piece to be cleaned in the solution(coat hangar wire works for me) the (-)side of the charger connects to the piece you want to clean.
I did the doors half at a time,do one side and turn over and do the other side,fenders the same way,you will have a small section in the middle of the fenders that you can't get in the tank,it's in the middle of the part so is easy to get with a wire wheel or brush.
I think the garbage can will work for the radio boxes.
Try it you'll be glad you did,and when your finished there are no unused chemicals laying around.
Need any more help I'll be glad to help. Us old pilots and geezers got to stick together.
PG.