Saw your detailed posts on it from awhile back, would definitely be looking forward to a full suggestion if you decide to make it man! Its definitely one of the planes that getting exact info on is a bit hard and especially scarce given some things were just mock ups and all, but fingers crossed for a little Yak-141 treatment and some (hopium) AMRAAMs…
(Very intrigued by this new info you mention, what kinda info is now available?)
For starters, all this is from Paul Metz’s book on the F-20 that released back in August of 2023:
There’s proper info on what a production-level cockpit would look like for the 2nd/3rd prototype, as well as proposed 4th prototype and Air Defense Fighter variant.
There’s info on proposed CAS-focused variants, the potential “big-wing” F-20, cockpit displays, radar warning system, countermeasures, confirmation of compatibility with AIM-9L, radar modes, etc
What tree? I’m assuming Britain b/c of the LR Defender 90 pickup. Oh, also, I realized it has the IRST unit, so it can track, just not radar track, technically speaking, making it much better.