I always used Fortes on the rovers with Head gasket failure but it seems to have vanished locally.
What is the recommended product for flushing the mayo out of coolant pipes and radiator - say after oil cooler failure?
God i hate that bloody Mayo 
After the oil cooler failed on mine, I flushed the whole system, including taking the pipe off the heater matrix and flushed water round the system (Not under big pressure!!!) about 15 times in total. After 2 days there was still a fair amount of mayo in the header tank. The mayo just sticks everywhere so it's important to get as much out as you can. I'll probably be shot down in flames for this but I added 2 mugs of diesel in the final top up, no coolant....drove for about 30 miles, repeated the flush another 5 times and you can hardly see a trace of mayo now. Someone gave me the tip for using a little diesel as this has good cleaning agents in. Well it done the trick here ok, where as my average temp was 95/97C it now sits at 90C happily on tick over.
It's important to make sure the rad is fully discharged too, it didn't seem enough to just drop the lower hose. Get the engine upto working temp under pressure, take off the top rad pipe that connects to the expansion tank (Being very careful, watch the mayo scream out. Gradully keep filling the expansion tank untill the water runs clear. Do this as many times as you can. Rad flush didn't touch the mayo as well as the dielsel did. It spewed it out after a 30 mile run. Now, clean as a whistle!
Hope this helps