If you buy the marriage cert, it will give you John's age, occupation and father's name/occupation. That should make it possible to look for hil on the 1901 census (even with a relatively common name like Murray!) and work backwards.
The GRO reference is Manchester 8d 471. (From Free BMD
http://freebmd.rootsweb.com) You can order the cert online at
http://www.1837online.com/Trace2web/, or by post from Manchester record office:
Heron House, 47 Lloyd Street, Manchester, M2 5LE.
Tel: 0161 234 7878. Fax: 0161 234 7888.
Hope this helps!
Rambler