I don't have an inventory of which vehicles were used in which squadrons or troops. The realiaty is that there were relatively rew MkVII gun tanks in service in North West Europe - most MkVIIs went to the crocodile regiments. From records it would appear that by December 1944 the 6th Guards Tank brigade as a whole only had 12 MkVIIs. If MkVIIs were really this scarce its probably reasonable to assume that the 'senior' members of the regiment would take first pick and so they are more likely to be found within Regimental H.Q. and Squadron H.Q. etc.
The only Scots Guards MkVII I have 'full' details for is:
T173143, BEN NEVIS, Regimental HQ, This had the earlier pattern MkIV style air intakes and no bulges on turret front.