Monster 620 lock set replacement

Hi, I have purchased a Monster 620 which was stolen recovered, the ignition has been damaged and is useless. I have purchased a complete used lock set including the immobilizer ring that sits with the ign switch. I have wired it up and all works except starter button. Before I delve deeper , have I got all I need. I have 1 x black key with the replacement locks. I have the keys for the original set but the ign is toast. Am I going wrong somewhere? Thanks in advance