To the best of my knowledge, the only workshop manual for the Morgan four wheeler was the one written by R. M. Clarkson and published as part of the Autobooks series. It covers the period 1936 to 1982ish so wouldn't directly cover your Dads car with a Zetec engine but does include a section on rebuilding the front suspension (although DaveW has published a comprehensive 'how to' on these pages which cover it in greater detail)
Happy to make a copy of the relevant part of the Autobooks manual - I'm based in Holywell so just over the river from the Wirral!
Arwyn
