Classic Series DSC PC2550 compatibility

[thumperstrauss]

Have you used a DSC Classic Series with a Konnected  Interface Kit. I want to make sure it is not too old to work.  It is the DSC PC2550 rev 06P (circa 1990). I watched the videos and understand the process in general. Just want to avoid surprises. Like, can I add two Interface Kits to that DSC?