afb1,
Installing media gateways is not difficult but you do have to gather all the information from your customer and IT. Is this a G450? Do they have a current core server or set of core servers this will hang off of? Is this a remote site that would need to be survivable if it loses connection to the core server/servers? That requires an S8300 and that is even more involved but not too difficult. What release of software are they currently running? IP address for the GW, subnet mask, default gateway address and hostname. Make sure the hostname and IP are added to the DNS. Once you know more post your next set of questions.