TR60SN 09D Valve Body Differences

[TassiePorsche]

I'm about to replace my valve body on my 2004 Cayenne Turbo, however this is quite confusing as it seems there are multiple different version of valve bodies with the same part number (955 325 039 00 )

From what I have found in researching, there are three visually different versions of this valve body, each pictured below.

 

 

As you can see, there are two versions which have an additional 'port' or hole, one of these has a metal plate covering it, where as the other is left open. Finally, the third version has no port or opening at all.

I ordered the original part number valve body for my 04 turbo, and I have received the variant in the first picture (3 port). Until I remove the transmission pan to do the replacement, I won't know whether or not this is the same or different as mine. 

Some things I have read suggest that the valve body simply had a different casting in newer years and these are interchangeable without an issue. What it says in the photo above seems to contradict this though, and suggests it is crucial that you use the same as what your car had originally. 

Another uncertainty regarding this is the TCU, and whether or not this needs to be changed or updated to suit different valve body versions. Searching for these questions on the internet is met with very little luck, and many contradictory answers.

I would be extremely grateful if someone who is knowledgeable in this area can shed some light on this for me, as at this point I'm totally unsure about what is true and what isn't.