Well i thought id post this for anyone who may be looking to upgrade at a later date.
i have reciently changed my OEM radiator for an aluminium twin core radiator.
Due to the lack of dual core or tripple core aluminium radiators that fit the fto i had to look elsewhere for a solution.
First off anything bigger than a single core radiator wont fir with the oem fan's so you will need slimline fan's.
Having tried radiators from countless car's we finally found one that would fit (issue being the height of the front end of the fto is so low.) a dual core radiator from a Honda CRX fitted within the space perfectly.
Some modification was needed.
The water feed and return are on the wrong side of the radiator and the mounts will need to be moved. But they are more redily available and of better performance tham whats thete for the fto.