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"the tank might actually be a necessary part" my ass.
Figured it out, takes a little more partsforming than I thought (thought it should have been expected given how much partsforming these things use). In one of the accessory packs (can't remember from which figure, I kinda had them all scattered on a table) there's a peg extender you stick on thunder's head peg which gives enough room to fit red on.
