The only thing that I can suggest is that with the system being existing, there must have already been trunks connected to it. If you are lucky, and I say that with a capital "L", you should be able to simply trace the jumpers from the existing network interface for the original trunks to locate their position on the system's blocks. If this is your case, you can simply move the jumpers to the new network interface.
I'd be willing to bet that the original system was set up for ground-start trunks and I'll throw another dollar into my bet that the new lines ordered by the customer are not ground-start trunks (cheaper is better, right?).
If I had only minimal system experience, I'd steer clear of this situation. If you don't truly understand the concept of PBX trunking, ground-start, trunk polarity, etc., you are setting yourself up for a big headache.
Mitel's hotel/motel systems are remarkably simple for people who know them, but they are a daunting task for those who don't.
I absolutely HATE replies where we tell people to "call a professional", but when dealing with the SX-50 and having no experience, I just can't think of anything else to say.
By the way, your question isn't "dumb" at all. At least you had the foresight to ask first before you landed yourself into a den of snakes.
