sight glass

My eyes are bad, I repaired leak in line, it's so hard to tell fluid in the glass, I may overfilled, or lost way more than I thought..is there any kind of a trick with a colored light? Permatran 3 is hard to tell, wish it had a dip stick.

What’s involved to replace a foggy hydraulic sight glass on 2014 t650?

Does anyone know what size sight glass we have and whether it is threaded or pressed in. Mine might be leaking and I would like a spare or two before I touch it. I tried measuring it today at 1.173", but I couldn't get real close to say it was accurate. The screw in versions are about $10 for...