The trouble with browsing the ashcroft website is the pain I will later feel explaining to my mrs why I bought XXX new wizzy gizmo! In the 30 seconds I just gave it, I found an r380 oil cooler... sounds like a must-have to me!! ha!
Amen!! "But darling, I really, really do need this new whizzy gizmo" - go on, you know you want to !!
the oil cooler is going to be more or less essential in your application - with all that grunt from that rather nice V8 - take it from an expert (me - ha ha!!)
seriously, before you buy a cooler - have a look here....
http://www.alutec.co.uk/?page=main
made me a custom cooler for my auto upgrade for about £160.... ( I.E:- cheaper than a new standard size one )