i have a pro x 440 fan and i want to put a 600 in and i can't find a place that sells tunnels and how much a tunnel would cost

So put the 600 in, why would you need a tunnel? What's wrong with your tunnel?

cause i don't belive the sled has coolers cause it has a fan colled engine

You should still be able to add the coolers to the stock tunnel.

I converted my '02 440 fan to liquid this past offseason. You'll need the bulkhead cooler, tunnel coolers, rivets and hoses. Let me know if you need any help.

SK.

yeah he's right.. i am in the process of doing that same thing right now... add coolers and hoses and you and make liquid.. you just have to find a wiring harness for the 600. just keep checking on here for parts this is where i got most of mine to do swich.