Yes, you have the correct eras listed and all four would have the same OD Green paint.  The M3 Lee and M3 Stuart could be in desert colors as they were also used in N. Africa by the British.

For more info do a google search for each vehicle and you will find all sorts of info.

Yeap what Gino said...

Here's a good site I use. He hasn't updated it in forever though: 

http://usarmymodels.com/

Steven Zaloga had a really good article on shades of olive drab but it seems to have been taken down.