I'm afraid that the entire series of lat war RLM colours is a proverbial "can of worms". I've looked into this in some depth and still remain confused. I'm away from home at the moment so rather than giving a lengthy response with no references I'd suggest a read of this article by David Brown. His opinion is well respected and there is nothing controversial in it.
Luftwaffe Late War Fighter Camouflage - Part Three
Here is a relevant quote
"September 1944
Factory Camouflage Directive, Fw 190 A:
It is most probable that this document or a related order (possibly a document only and not an Oberflächenschutzliste), existed in some form and specified the 75/83 scheme for the Fw 190 D-9 as well (see above comments).
COMMENT: First operational use of the Dora took place in early October 1944 with III./JG 54 whose aircraft were camouflaged in the 75/83 scheme that is well documented with photographic evidence.(Smith and Creek, 1986, p.10). However, a change occurred in the camouflage colours used in early 1945, from the standard 75/83 scheme to the 81/82 combination, and it is most probable that a variety of transition schemes existed (e.g., 81/83, 82/83, 75/81, etc.) "
That's clear as mud then!
It would appear that RLM 83 is favourite. RLM 83 is only ever described as green in surviving documents. RLM81,as you rightly say,has a brownish or olive tinge. It was described by Messerschmitt as "braunviolet". I can't look up other descriptions at the moment,but,despite variations in the hues of these paints depending on the manufacturer,none imply a really green colour. I'd go with 82 or 83 as everyone from Merrick to Crandall by way of Brown and Ullmann thinks there was a green colour in that scheme!
I notice your colour call also gives the grey as RLM 74. I've only remember seeing reference to RLM 75 as the grey in the context of these schemes (as per Brown above). The standard was therefore 75/83 over 76. I'll look into the "grey variations" when I get home towards the end of the week and let you know what I find.
I may do one of these myself (I've always liked "Red 1") so it'll be a bit of a refresher for me and also the whole point of a group build!
I expect there will be plenty of debate about this as we start the GB. It's important to remember that we can only ever go with a best estimate based on available data,unless someone turns up with a portfolio of colour photos. We shouldn't beat ourselves up too much about exact shades as the truth is...noone knows!
Cheers
Steve
Edit: I notice the call on the Pacific Coast Ta152 is 75/82 and I bet that was well researched.