I take it this is a standard CM7000 radio body and head only? Its not an A/A4 repeater or any of the other dozen or so variations consisting of either one or two mobile radio bodies and/or one or two CH600 or CH650 Puma handhelds in a cabinet?
If its just the mobile radio (and leaving aside the change its an AM/FM conversion!), then you require the correct programming software, a RIB (interface box) and an old PC to run it on. Bear in mind that the software versions and the radio versions that are compatible were never properly documented, and there are lots of variations.
The 'good' news is that the interface is a simple MAX232 RS232 to TTL converter. The bad news is the radio end wiring is also very variable and documentation hard to come by (some radios will program from the head or the rear socket, some only one or the other!)
The online Pye Museum http://www.qsl.net/gm8aob/pages_2/CM7000.htm
has some programming info, plus a wealth of pictures identifying different Cleartone radio and repeater varients. I serviced all types of Public Safety/Emergency Service Cleartone systems many years ago, and can assure you they were a pig to work on, and a nightmare to program.
Interestingly, if you look here
this is one that I worked on - Literally! The tested sticker in the corner is one of mine!
Bench 40, MB (Martin Barfield), ntl Kippax maintenance center.