Just keep the revs below 5k and you should be fine.
Alternatively... Baines will knock up a rad and lines for a fair bit less than the DP kit, then I think all you'll need is the diverter plate and a bracket. Probably the cheapest way if you can't find 2nd hand stuff.
I'm strapping the conservatory fan to mine for Snet - D'ya reckon it might make me go faster if I aim it in the right direction ? Wind powered 583 anyone ? ( maybe that was just the curry )
I have a oil cooler from a monster 750 with hoses in excellent nick. I was intending fitting it to my s4 but not sure yet. If any one wants it for £100 which is cheap as dp ones are £300 .I will sell to buy some rear sets.