I know there is a genuine reluctance to buy parts off eBay, but this radiator seems an exceptional deal.
http://www.ebay.com/itm/230561529705...1#ht_500wt_922
The standard 55 radiator has a good surface area exposed to airflow and this just seems to make that fact better. I ran a modified ( fitted with four cores ) 55 radiator in front of a 351 Cleveland with an FMX and it never ever boiled over in any conditions. I did run a pusher electric fan in front of it along with a engine mounted flex fan. I do think this is a better rad than I was using though I haven't seen one in the flesh - just going by sellers description.
Regards