When the MMC was recreating my destroyed Plus 8 in 2002/3, one of the many person design team was the Mark Baldwin, the Factory service chief. We discussed this area at length. I was very leery about the post June 1993 brake booster (which I swear by now) and dear Mark was concerned about the reservoir as my planned bhp was higher than standard and heat is function of bhp
. and my original year had a twin branch manifolds system. He was right I had the melting brake reservoir on one side and a new often melting windscreen washer on the other. I admit to a dislike of wrapping things on my cars.
Baldwin checked what the MMC had and we designed workarounds, similar with what had worked for him before in his MMC crew team racing days We removed the brake reservoir, installed adapters
sold everywhere and stainless sleeve-hosed them to a remote Aero 8 brake reservoir..that feeds both brake and clutch hydrualics. I keep meaning to get something prettier, but I forget.

On the other side, I switched back to the small windscreen fluid reservoir that is far enough away from the exhaust NOT to melt (I admit to keeping on eye on how full that reservoir is. Almost empty reservoirs melt faster!.
Check
https://www.gomog.com/allmorgan/RemoteBrakeReservoir.html Scroll down for English.
L.