Looking it over I see what I had looked up, kinda, here is the picture.
Attachment 55687
There is nothing on the back side of the fan shroud.
and if I remember correctly, that case vent box is suppose to be cleaned every so often, and my mind thinks there is some type of filter material used inside it.
Attachment 55688
Taken from right side of engine, and the first pic was taken from the left side (3 and 4) cylinders.
I have no idea if it has ran all this time with out a oil cooler, I highly doubt it because they did take a few trips on it, so I have heard, so I will have to go with the fact that the old cooler was removed because of leaks, or I pray that was the case.
Now I got to get a new one. From what I read I would not benefit a lot with a external mounted cooler, but would do better with a full flow external oil filter set up with just the stock oil cooler.
If this is a aftermarket fan shroud, did the copy the venting and flanges of the original one ? I just read how well the Germans design the fan shroud to cool the engine, and why the internal cooler in the shroud caused the #3 cylinder to run hotter than others, lack of air flow to cool it, so I have learned a lot today.
We can do so much to look cool, think we are doing the engine better, and the reality is it all just cost money and really does nothing, sometimes create problems rather than fix them....