RE: silicone implants
'Coating' a circuit board isn't as simple as it may sound, there are a few "got'cha's" you should think about. On almost all receivers there are connections that need to be made/unmade at one time or another (servo slots, for one, crystals for another). If you can figure a way to be able to do that, then great. Another "got'cha" is that whatever you use to do that 'coating' has to be compatible with what it's 'coating'. Most silicon sealants that I've used have had a sort of vinegar smell to them. That odor means that they contain an acid, and it will eventually 'eat' anything metal that it coats, and can become conductive under the right circumstances.
Of course, if you have to have it worked on for some reason, the one doing the work isn't gonna be too happy with a receiver being 'coated'. And while I haven't asked, I would bet that the warranty just flew out the window, sort of. So, if you get around those thingys, it'll probably work okay.
- 'Doc