Easy, but you cant really see what your doing. Long arms and a 13mm rachet spanner really help

3 x 13mm bolts around the housing roughly 12 o clock - I used a bendy socket extension as spannering is slow even with the rachet spanner, 9 oclock and 6 oclock - which as the earth wire bolted to it.

Then a 10or11mm and a 13mm on the postive feeds

Unclip the the expansion tank and jiggle out

PS disconnect battery first of course

 

Many thanks will give it a go !!!

 

Managed to get one bolt out --- 12 oclock one I think...the one below wiring loom...the others are a right b%$%^ard to get too any other top tips most welcome.........