Try Barry Beldam's website for marking placement. I took a quick look and found a colour profile for a British Columbic Sherman Ic, so there might be more.
http://www.armouredacorn.com/reference/bam/8th-armd-bde---complete.pdf#!canadian-vehicle-markings/c1oy0
Having a mixture of Shermans and Fireflies was the norm for Canadian tank regiments for NW Europe. The only thing that changed was that initially troop leaders were given the 17pdr. When the Germans realized these up-gunned tanks needed to be dealt with first, allied officers were being lost at an alarming rate, so Fireflies were assigned to lower troop ranks (one Firefly per troop, but eventually two would be available).
Being the junior regiment of 4th CAD, all their Shermans would have white 53 on a red background.
The regiment would be made up of A, B, and C squadrons, along with the regimental HQ squadron.
regards,
Jack