Yes, those are outside casing temps.

I know they will not show actual internal operating temps, that is why I was wondering if anyone knew what range the external temps would generally be.
My gut tells me, even though they indicate there is something burning in there, the temps look low for as high a temp as should be on the inside. I just do not know what the delta-T would be, or if there even is one. The highest reading I got was dead center on the bottom of the CAT casing.

So if anyone has checked the casing temp of a new CAT. I would be very thankful if you were to share.