by suffix i'm assuming your referring to the last 2 numbers on the
convergence ICs...
IC STK392-020 in this case "20".

another question is.. if there's 3 guns.... there's only 2 convergence
ICs.

actually.. i thought about this.. on a regular CRT.. green is the
center and red an blue converge on that.. is rear projection similar?

and if so... i'm assuming 1 IC controls red and the other controls
blue.

that being said.. is there any way to tell which is the RED convergence
IC? or am i completely incorrect in my assumption.

thx.
keith