I have meantioned befor that we did things with "Ranger Eyes" tape on M-60 GPMGs and on M-16A1s.
We found this helpful especially at or just after twilght when the Mark I Eyeball wsa not finished transitioning to "night vision" mode.
I used Beta Lights (European Tritium Lights) on a 9x19 Star Starlight in 1974 or 75. The had the two dot system with one dot on the rear sight below the notch and one near the top of the front sight so the sight picture was : and it work very well all the way out to the 25 meters I got to use them at.
Stateside in the late 1970's I used a glow in the dark paint on some pistol sights, trying front sight only, area between frontsight and ejection port for about an inch, rear sight only, trying three dot ( two rear one front) and inverted T where the horizontal bar was just below the rear and vetical on the front sight and the two dot system.
All suffered from the need to be charged. About the only system I saw that sort of worked was a friend kept a little Beretta .22Short semi auto in a car's ashtray that had a light in it that was on anytime the dash board lights were on. When he got to where he was going he dropped the Minx in his pocket and had a couple of hours.
We actually tried equiping a holster with an old wheat lamp bulb ( before LED became widely valable) to charge just a front sight but we kept breaking the bulb and worried about it being hot and about it lighting us up when we pulled the gun, a system to allow the bulb to be shut off proved to cumbersome for the tech of the time.
My first state side use of tritium was an old Single Point scope. I had some experience with the non powered models and we came up with a system that used GI flash light bulbs hundred mile and hour tape and BA 30 taped to the scope that sort of worked and this we later improved on with a wheat bulb powered system using a short section of PVC pipe and cap and glueing a battery holder and switch to the PVC. We even placed Ranger Eyes tape in the PVC cap so we could have light for the dot with out running the wheat light bulb continuously. Hot stuff in the '70's, but the tritium scope in 79 was "more better" by leaps and bounds.......just as tritium would be over glow in the dark paint.
Paint kits to make glow in the dark dots that need charging have been around since the 1980's atleast and I see kits at gunshows having multiple colors still.
-kBob