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I'm assuming the black camo would be the Mickey Mouse pattern?
Not necessarily. It would be slightly more likely to be the MTP46 sheme. You can see the relevant section of the actual pamphlet here:
http://bcoy1cpb.pacdat.net/mtp_46_pt_4a_painting_mt.htmQuoted Text
would the limber carrier and gun be light mud, any camo on these?
Yes and Yes.
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And would these light mud vehicles be the same colour underneath and inside or would they have started out green?
They would have started out some other colour, either SCC2 Service Colour (= dogsh*t brown) or Light Stone. Light Mud was a theatre colour and only provided locally.
Hey, waitaminute...
If Light Mud was a local colour and the Brits got vehicles painted at the factory or depot (and they did) then the depot to paint the Light Mud would have had to be in North Africa or Sicily. The Canadian troops didn't land in North Aftrica before the invasion, coming straight from England. The G3/G4 scheme had been out of fashion for 2 years at that point, so, I amend my previous guess! I think the Canadian vehicles all landed in SCC2 with maybe the SCC1a camouflage in the MTP46 or Mickey Mouse Ear pattern.
Bugger, why didn't I think of that before?
The Brits did paint their kit in Light Mud before the invasion, but the Canadians didn't get the chance. They'd have most likely gone in with brown vehicles, the current standard in England. They could have been in Light Stone, but vehicles going to Tunisia were already being painted in greens and darker colours so the Sicilian vehciles were probably the same, darker tones.
Your Light Mud model isn't wrong, it is just more appropriate for later in the Campaign, say the time of the invasion of the Italian mainland. Our units had had several weeks off between the end of Sicicly and their beginning in Italy. That would have been time to repaint.
So, in answer to your original question:
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And would these light mud vehicles be the same colour underneath and inside or would they have started out green?
They would have been brown or light stone and generally the interiors & undersides of the vehicle & limber would remain that colour throughout the vehicle's life.
If you go to this page on the Maple Leaf Up forum:
http://www.mapleleafup.org/forums/showthread.php?t=2961you can see several photos and a good discussion of how the patterns should look. There are three photos in the middle of the page from "Cletrac"
that should not be taken as accurate. These are of an Australian FAT and do not comply with any Brit pattern. They might be OK for an Aussie pattern in the pacific, but not for anything in Italy or NW Europe.
Paul