Just to confirm what you suspected after seeing the gravestone photograph, John Bell is buried in the old Kirkhill ground next to the river Clyde. Here is the entry from the gravediggers Day Book -
JOHN BELL, house proprietor. Wishaw, aged 78 years, widower.
Parents - William Bell & Margaret Gourlie.
Interred in Clyde burial ground on 23rd November 1868.
Other entries for the Clyde burial ground that may be of interest to you -
ELIZABETH HAMILTON BELL, Wishaw, aged 65 years, unmarried.
Parents - William Bell & Helen Hamilton.
Interred 31st March 1914.
WILLIAM BELL, wood merchant, Wishaw, aged 55 years, married.
Parents - John Bell & Janet Morton.
Interred 3rd February 1872.
JESSIE BELL, Wishaw, aged 49 years, unmarried.
Parents - John Bell & Janet Morton.
Interred 10th June 1872.
JOHN MORTON BELL, Wishaw, aged 5 years.
Parents - John Bell & Margaret Hamilton.
Interred 1st December 1875.
There are a couple of entries for children of Thomas Bell & Jane Ferguson, ring any bells?

Finally, an entry from the Day Book for the private burial ground at Cambusnethan, next to the municipal cemetery -
THE LEG OF ARCHIBALD BELL.
Parents - Archibald Bell & Martha Aitken.
Interred in plot No.6, 28th September 1870.
No mention of what happened to the rest of the unfortunate Archibald!