Need a little 4WD troubleshooting help.

First what I have:
2001 RS 3.2 Manual
4" custom suspension lift
3" custom body lift
305/70/16's on 16x8's = 33's
Manual hubs

The 4wd started flashing about 1 year ago. Cleaning the connector didn't fix, so I swapped the axle control for an earlier models (free part). I soon found that early models have two vacuum hoses vs. the later models one, so I did the modification. Of course I used the older module since the modification will not work on the newer style module.

http://www.4x4wire.com/isuzu/tech/fwd_lockout/?

It seems to pull now however I cannot shift from hi to lo and really need it with the 33's and stock gears. Of course the 4WD light still flashes; I assume this is because the module swap didn't allow for ellectrical connection. The early model has a 2 pin and my 2001 is a 4 pin.

Can someone explain how the transfer case solenoid works in this thing and what might be wrong? Please?