[Haskell-cafe] Parsec question

Hi, I'm porting a parser over from an OCamllex/Ocamlyacc version and I'm using Parsec for both the tokenizer and the resulting token stream parser. I have both of them working fine, but now my question is: how do I combine them? I can't quite figure out how to say "take the output from this GenParser Char () Tok and use it as the input for this GenParser Tok () ParserOutput". Well, I have figured out an ugly way involving manually starting up both parsers, but it makes position calculations very complex. I suspect I'm missing something. Ideas?