[tamiya fan]

I know this thread is older, but might help someone out. I think I know what you want to do is make your truck fifth wheel operate the support legs on the trailer? (via slotted slider piece) It takes more than that piece alone. The Support leg kit comes with 2 sets of plastic sprues in it, and you will have to by both plus some other hardware (unless you have some extra screws and small ball joint) I think Tamiya did it that way on purpose. I haven't priced it out but would probably cost almost as much as the whole kit with out the extra parts. (which might come in handy some day?) Unless you know some one nice with the extras!