I think you may have to have it done at a dealer but you could try emailing customer services/Neil Turner: nturner @ lotuscars . com or customerservices @ lotuscars . com to find out.
Rowland Leftly is (I think) the main outward facing contact at Lotus Motorsport.
Thanks for that.
Someone advised they did do it there and it would make sense to save paying a dealer …anyway I have contacted them and await results.
They do cater for servicing at the factory so i can’t see why not?
Finally got round to booking my car in to have the recall work done at Strattons , i asked them to replace the towing post while the front clam is off , just got an email from them saying the front clam dosnt need to come off to do the work 
My understanding is it’s pretty well impossible to get to the unions on the coolers without removing the clam, I asked a couple of dealers about this before I had mine done as clearly would have preferred to not have the clam removed… Guess Strattons must have done a few replacements by now though…