My cruiser had been getting flaky about changing out of 4wd. It was an intermittent problem & it took a while to work out that the 4wd control computer was crapping out & not switching the vacuum solenoid valves that feed the diaphragm that shifts the transfer case. Given my electric hubs are long gone it was well overdue to simplify the system. So the box of electronics was replaced with a simple changeover relay. This also means it doesn't automatically switch into 4wd when in low range.
Rewired the 4wd warning light also. I had installed a bank of relay sockets under the hood a while back to feed the spotlights & locker, & had left a spare one, so that made the relay install fairly tidy.
While I had the dash out I upgraded the old speakers too.
Cheers
Clint