Hi,
I too have been looking into tippers, Ive got fed up with chucking logs out the back by hand. Id love a 130 but they seem a bit big for manoeuvring round woodlands, ive seen a landy on ebay (quite a while ago) where the original hi cap tub had been converted to tip, and I've wondered how bigger job it would be. Ive looked a few with custom made tipping backs but there very pricey and think I need to cut a bit more wood before I can afford one.
Good luck, Id be interested to know how you get on.