Suttling House, St James’s Palace.

[hanes teulu]

Re."tilt yard" (now found the newspaper item), I took this to mean that the Suttling House looked out on Horse Guards rather than Whitheall.

[Iain...]

Wow…, and the waters get muddier !  Thank you very much for that ! 
And I’ll obviously need some time to research it.

Lol…, and just as I started writing this, I received a message from the NWF with the following.

“Hi Iain - from memory, I think I recall Brice's establishment as being located in 'the tiltyard at Horseguards' (I'm not sure if this is the same place as St James's Palace?). Anyway, here's a link that might help and Google may reveal more references:
https://www.google.co.uk/url?sa=t&source=web&rct=j&url=http://www.british-history.ac.uk/survey-london/vol16/pt1/pp5-16&ved=0ahUKEwj726iU943XAhUMaVAKHc8mD3oQFggmMAA&usg=AOvVaw1oSPWlxEfwB5PvNhfaOFZU

Roots Chat…, what a wonderful website ! 

[hanes teulu]

His census entry follows an occupier of part (" rooms and an attic) of the Horse Guards Building. Is it possible to pin that down? Is it the "Old War Office Building" - had started checking out "Adjutant General" But must disappear now (allotment duties call!).
 
I cannot see an Upper Charles Streeton the 1837 map of London.

[StevieSteve]

Is it the "Old War Office Building"

No, that's on the opposite side of Whitehall

[StevieSteve]

Quite a lot here (which I haven't read)

http://www.british-history.ac.uk/survey-london/vol16/pt1/pp5-16

[hanes teulu]

SteveSteve's link mentions the Commander in Chief's Office

From the same Publication (1845) that provided details of the Adjutant General's Office

"Commander in Chief's Office"

House or Building - Part of the Horse Guard's Building
Purpose - Commander in Chief's Office
Person's Residing - (1) Mrs Ferguson, housekeeper and two servants. Two rooms in the attic, kitchen and servants' room (2) Mr Whitmore, Office Keeper, wife and son. One room underground and two on the upper floor"

Yet to spot either in the '41 Census

I raised the query about the the old War Office, off Horse Guards Ave, possibly being the old Horse Guard Building after reading a "google books" reference - but didn't follow it up there and then (allotment was calling). Just checked and the address before the Adjutant General on the 1841 Census is The War Office.

Now, typically, cannot find item!!

[hanes teulu]

Kelly's Map, London 1857

http://www.mapco.net/kelly1857/kelly11b.htm

Shows a Charles Street, Whitehall - yet to pinpoint an Upper Charles Street

[Iain...]

Amazing...

Thanks everyone for all that…
Things are certainly looking a little less muddy.   I played the pipes dozens of times in the Officer’s Mess at Saint James’s and just couldn’t for the life of me see how their windows could have looked onto such a premises. (with a court and railings)   
https://www.dropbox.com/sc/o7dyzzs5ih8niq4/AAC6g4k932bIoFowIJ1RLTwFa

Horse Guards looks more promising !
Having served in the same ‘Light Company’ as Brice, one tends to get the impression that the Army just don’t make clerical errors !   
Looks like I’ve another think coming.

[hanes teulu]

Looks like the reference I found to the "old" War Office occupying the Horse Guards' Building should read the "old,old War Office"?

The 1841 Census War Office, Horse Guards address shows a "Mary Wheeler". Several 1837 newspapers reported the death of "Mr Wheeler, of the War Office, Horseguards."