How to distinguish between a 3rd gen and 2nd gen 13b
 

I am asking a friend to pickup a 3rd gen13b engine/gearbox from a junkyard mainly for spare parts. It is for my 3rd gen. I dont want him to get a 2nd gen 13b/gearbox by mistake. Are there any differences that can be seen visually such as stamped codes or external hardware that he can look for to distinguish.

Also, are there any tips anyone can give for things to look for on the outside that would indicate the internal condition of the engine such as oily ports etc.

You'll very rarely see a 3rd gen motor in a second gen and visa versa,
assume if its in the chassis of the car he's looking for that its the correct
engine. The internals on these are slightly different as well as the front
irons/covers. There's probably a few other differences, such as the twin
scroll on the REW that you can quickly identify it. Try using the search,
I'm sure this questions been answered a hundred times already.

Hope that helps.