2009 E67 VVT Capable, or 2010+ only?

Hi all. I have spent a ton of time researching, and have a few questions outstanding. Checking path suggestions to perform what I want to do. Appreciate your input before I continue to purchase parts, the knowledgebase here is tremendous. Apology in advance for posting this in an E67 section, as there is a pinch more to it than just that.

Stock 2009 Colorado V8:
Have: 5.3L (E67 ECM) + 4L60E T42 TCM (stock as-built config)
Want: 6.2L (use same E67 ECM) + 6L80E (internal T43 TCM)

Few others have done the 6L80E swap and appears that only CAN +/-, power, ground, brake signal, and park/neutral needs to be sent to the T43. Gravy. It is mentioned to "marry" the E67 and T43 together so they talk, not sure how to do, or if just OS/cal loading of the TCM through the ECM pass-through takes care of that?

I have asked this once historically 1-2 years ago, but checking to see if any updates. I plan to not change the engine and trans at the same time, would rather do step-wise to reduce complexity. Here are my concerns, and I really appreciate the insight to help this move forward:

1. I think all 6.2's are stock equipped with VVT (?). I'd like to be able to retain this, but unsure if able to, as I don't believe the 2009 E67 module has the VVT output driver in it? GM shows a different ECM service part number for 2010-12, as the 2010-12 came with a VVT 5.3L (LH9), as where my 2009 5.3L is non-VVT (LH8). Is VVT control able to be added and copied over from a 2010? Or should I just bank on converting the 6.2L to a non-VVT cam? I'd like to retain VVT is possible. I don't believe a 2010 E67 would play well with the rest of my stock truck if I tried that?
2009 Colorado V8 E67 service p/n: 12636659
2010-2012 Colorado V8 E67 service p/n: 12678513


2. For the 6L80 T43 TCM, it is strongly suggested to match model years from ECM to TCM for communication. Understood. I came across a 6L80e for $500, and it is a 2007. Can I simply update it's internal OS form 2007 to 2009 level to match the ECM OS year? I "think" all T43's 2007-2009 are same, but please confirm. I do have access to GM MDI and subscription.

Thanks again. Look forward to figuring this out.

Thanks a bunch.

vvt can be enabled on the 2009 colorado ecm with zero issues, simply adding 2 pins to the ecm and set the parameters in the tune and populate the tables and your good to go