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Fantastic reading.You've done a marvelous job in resurecting this set.
My comment that follows is mearly a suggestion.If you're unfamiliar with adjusting gray scale,I thought I might pass on some basics to help.
From some of the pictures you've attached do show that your gray scale is off on both ends.This may be just the pictures,but if what is shown is what you're seeing on the set when looking at the stairstep pattern,it looks to me as if both ends are off.That pattern should show shades of gray from black to white when properly calibrated.It looks bluish on one end and greenish on the other.If you're trying to approach the NTSC color temperature of D65 (6500K),what will help is a colorimeter.Doing it by eyeball is impossible.Prior to any adjustments to these areas,it's imperative that the Black and White (brightness and contrast) levels be adjusted properly.
There are two different adjustment points,the lower end using a 20IRE window pattern and the upper end using a 100IRE window pattern.Most sets have these controls,whether it be by analog pots pots or by service menu access in the newer digital sets.The lower end controls are called cut or bias or even screen by some manufacture while the upper end controls are called drive.If you have R G B for both end,great.Some sets only have two,just depends on the manufacture.
A bias light behind the tv or screen is not a reference for D65 adjustment puposes.It's there for overall viewing reference.
I've had the opportunity to calibrate a few CRT direct view sets and projectors over a span of about 6 years,using a Philips color analyzer and test pattern generator.Have also used patterns from A Video Standard and Video Essentials.The patterns from VE are very good.Getting the gray scale to track properly isn't always easy nor do sets hold them well.But,if this can be done,then the set's color will be as true as it can be,without being shaded.
Please do not take any of my comments or advice as criticism.On the contrary,I am just ecstatic to see life being brought back to these sets.I remember them fondly and have always been fascinated by television.I don't have the repair background that you obviously posses,but my curiosity as to why they all looked different pushed my desire to learn as much as a hobbiest/part time member of ISF could with respect to picture quality.
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