I am assuming that you saw this thread:
Dead Link Removed
If not, it is discussed in detail, there is a simple diagram and pics in there somewhere.
Also, I have posted the schematics for the 97 Control Trac in my photo gallery.
To summarize the thread (which is now 20 pages): You can disable the transfer case clutch by putting a switch or relay in line with the brown wire coming from the TOD (torque on demand) relay. Most of the people who have done the mod make the connection in the wire bundle under the drivers seat.
