I ... need the vaccum disconnect serviced.
My friend Mark's YJ kept melting the nylon (vacuum) lines running to the disconnect, which was obviously very frustrating. To solve the problem, I engineered a custom setup using two junkyard solenoids I had lying around my garage. I designed a vacuum harness which would send vacuum to the right place at the right time; it is controlled by a simple toggle switch mounted to the dash. Mark liked it because (a) this setup uses more durable (and pliable) rubber vacuum hoses, and (b) since he can control the front engagement independently of the transfer case, he gained the ability to run in 2LO when/if needed. The whole setup cost less than $20, and it has worked flawlessly for over a decade now.
Interested? If so, I may be able to dig up the vacuum diagram for you.