You souldn't have any problem hooking up a CoalTrol. If you just have the rheostats to control the feed and burn, You will LOVE the Coaltrol. My LL Hyfire is 1996 vintage and I put the CoalTrol on in about 10 mins. If you have the plugs on the cords. Otherwise, you will have to add plugs (Or get the plug kit from CoalTrol) to convert it.
It uses its OWN thermostat, you can't use a standard thermostat with it, but it controls extremely good, and you can control the feed, blowers, temp, etc..all from a remote location (it's not wireless, but has a 25' thermostat cord, but can be extended).