Hi Stuart -
It's obviously a wheel pants model from the attached image, some aircraft are missing the nose or main ones as well, at times, so a recent picture is always helpful.
As to whether the aircraft is an early or late model, I have no idea. I just copy the previous CFG entry and the aircraft adopts whatever model that had. Or if it is just a paint thing, then I may even have some paints that have the wrong details on there. There are very few pictures that show any roof windows, so that is a detail that might sometimes get missed.
If people spot that a detail is incorrect, or they think the colours are slightly off, they always have the option of clicking the first link and using One Click Repaint to adjust everything to their own tastes.
I don't make CFGs because I will often not install these for months, which is why I simply use a previous CFG entry when I get around to it. Not everybody will like that, but it's my approach. If it matters enough, and someone is happy to do the necessary research, they can always add one in a reply to the thread. They might even want to check that I have added whatever the right details are for each variation, early or late.
My aim is to have a Cessna shaped thing in the sim with a passable version of a real world livery. I'm a man of simple tastes. Once I have enough of them gathered up, I do a mass installation and create some 52-week flightplans that use the bases that I have researched for each one.