Dudeimanoldfart

Alright...hah my brother just recently told me he has had this small green plastic bong. I go to look at it and it's been sitting outside for god knows how long. I get it inside quickly as possible hah and check things out. It looks bad on the inside, but looks as if it can be fixed....hopefully....But there's tons of resin build up, and it's dirty and I really want to fix it up, hah like fixing up an old car or something. SO....any suggestions on how to wash it out? Or any fixer uper ideas? I know i've heard about boiling pipes and stuff but would that work with this small plastic green one?