Aww. I hate to say this, but I got that car chassis set and the power pack to go with it one Christmas - we're not far off in age. I took a stab at assembling it, but the instructions were just too difficult to follow. I think the pieces ended up in my brother's Lego bin. I don't know if he ever put it together. The power pack got good use, though - we built all sorts of simpler vehicles for it.