wasn't very helpful and did get a reply. Notwithstanding the lack of
support from the Haynes manual I did manage to change the pump but
can't remember how I did it at this distance in time.

I remember one that gave detailed instructions for a small job on the fuel
system.
I went to Cafco for the part, they sent me to a main dealer, who kept me
waiting but finally said "That part's now a flexible hose - I'll have to
sell you half a metre and you won't want it all, but it's only 34p and
it'll do you for next time as well - and it's much much easier to install"

How about this...
A friend an I were trying to change the starter motor on his VW Golf, all
was going according to plan, until we realised the Haynes manual omitted to
mention that one of the bolts holding the starter motor, was also part of
the engine mounting.
Getting this (last) bolt out was a right pain in the arse, we found out why
when the engine dropped about 2" (With me under it!!) when it finally came
out!

Sparks...