i have a 53 with a 56 235. i got a rad from ebay for 180 that way a 2 core, it was to thick
had to send it back, the bottem tank was way to wide, i would have had to cut out the welded cross bars and relocated the mounting brackets to get it to work. i ended up going with a used on.
i dont know if the 216s have this prob but with a later 235s you will prob need the single core
