During a recent overheating issue which was either the fan switch or the radiator cap (don’t ask me which because I changed both !) I also took the opportunity as the opportunity to change the coolant and junk all the 20 year old stuff for some silicone. it’s a plug and play thing to do with no surprises just replace like for like with the kit supplied. Nice to junk the hose covers at the same time as the silicone ones are more appealing on the eye.

They are made by a company called AS3 link below