Davieboy,
plot 47 St Patricks Dalziel, headstone for Alexander Allan died 15 Mar 1855, probably not the one for you,also Robert Allan 59yrs 6 Apr 1882, James Allan 77yrs 21 June 1906, Janet Lamb or Allan 79yrs 15 Sep 1907, Jeannie Gibson or Allan 84 yrs 27 April 1907, her parents were Jane Allan and Andrew Gibson, this info gleaned from Survey of St Patricks graveyard records, held at "Local Studies dept, Motherwell Heritage Centre."
Cheers