Bridge of Allan smiths

Wonderful what a fresh pair of eyes does.
Robert's interest in my HENDERSONs, sparked by his relationship to Margaret COUPER, who married Archibald son of Archibald HENDERSON  & Margaret McEWAN, has had both of us reviewing available information on the other children, and descendants, of Archibald and Margaret (McEWAN) H.

I'd previously thought that their son William must have died prior to 1855, probably prior to 1841, as there were no obvious sightings anywhere, other than an 1841 census entry that would otherwise fit apart from it being claimed as William born 1810 Cowie Hill, Logie, by a researcher as the son of William HENDERSON & Jean DUNCAN that I'd been in contact with back in 1994.

The more I look at this family, the more I'm becoming convinced that this is indeed my William.
Proof definitely lacking however as he does indeed appear to have died between 1846 and 1851, with Margaret also appearing to have inconveniently died between 1851 and 1855.

However, 5 of the 6 children emigrated to Melbourne, Australia in 1857, possibly with their grandmother Elizabeth SINCLAIR nee WATSON, so I'm now scurrying around seeing what else I can find.

Reviewing the 1994 correspondence I now note that the birthdate/place and parents of William were tentative at the time, not proven - so time to be checked where possible - and with a bit of luck a suitable dna candidate found for the HENDERSON DNA project? (The latter currently looks a little unlikely as far as Y-DNA is concerned, but possibly FamilyFinder may show a match to one or other of the 4 of us tested for this line over either Family Finder and/or Y-DNA)

Anyone know anything about a William HENDERSON, smith at Bridge of Allan between 1841 and 1851 in particular?