I have used a 200tdi/300tdi in some hot places.
I found that an extra row added to the core of the radiator worked well, or for 50+, simply find a 2.5 TD rad out of an RRC and add an extra row. This rad is about as thick as they come and yet still fits in the 'standard' frame.
The 50+ was whilst working for the BGS in the Danekil, where we had highs of 55
Whilst working in Aus, up in the Northern Territories, with highs of 42 and average of 35, our 300 tdi 130 (towing a 2 tonne chipper) never had issues with the standard rad
All temps in Centigrade