Scammell R100 "When in doubt brew up" and Sherman III question/help

[TISO]

Can anyone identify this vehicle and /or Shermann III?

Need help with markings.

 

I managed to get (thanks Hannants) Echelon Fine Decals set D726018 for "Scamell Pioneer and Sherman" in anticipation of IBG Scammel TRMU in one true scale.

They themselves wrote on their micro instructions which are size of a postage stamp: "The most incomplete marking set for the Sherman & Scamemell aficionados... Oh what a heck, eh?" 

https://www.hannants.co.uk/product/D726018?result-token=hozYi

 

OK this is obviously R100 artillery tractor and not TRMU (curved corner above the chap with a mug and lenght of superstructure aft of the door).

The artwork on the door matches. Unfortunatly there is only caricatures of 2 chaps (supposedly for Sherman III) and inscription "Would you like a cup of hot tea, old chap". No other markings like WD number unit markings etc are provided.

Help please.

 

Decals and the real thing:

 

source for the photo: http://www.mapleleafup.net/forums/showthread.php?t=30722

Edited February 3, 2021 by TISO