I had a 3.9i in my 110 csw (replaced the old 3.5) , I had a 13 row mocal oil cooler, standard viscous fan and the normal size V8 rad(with one extra row) that was able to handle 45C towing a 3.5 ton load with no problems . So it would seem that if you have the standard V8 rad , and a similar oil cooler it should be able to cope easily . Aussie spec V8 have the a/c condensor in front of rad and they also dont suffer from o/heating , the underbonnet temp thing is a problem in Australia as it heats the footwells, and seatbase to a level where you cant touch them , luckily the csw was fully carpeted, I dont know of anyone successfully overcoming the problem. Wrapping the exhaust , and putting vents in rear of bonnet were some.