I have the Mac's tank and a Napa overflow bottle in mine. Kinda have a little write-up on it here -> viewtopic.php?f=7&t=8051&st=0&sk=t&sd=a&start=165= . I did not need any special fittings to install mine. Eagle is correct - the tank will push out fluid when hot. Not sure why it doesn't act like a closed system :dunno: . I would have gotten the open radiator, if they had had them in stock, looking back on it now. It does look nice - but it has burned me on a few occasions. I used PIKE and Chico's write-ups to get mine set up <- thanks guys :cheers:. Be sure to search their posts too - Rich