Yo Rich,
Welcome!
This is an excerpt of, "Four Wheel Drive (4X4) General Information, Operation & Troubleshooting TSB 92-1-8 for 92 & Prior Year Bronco, Bronco II, etc. by Ford
http://web.archive.org/web/20100923194404/http://ylobronc.users.superford.org/documents/electric1356/elec1356.htm
via Dustin
Most common reasons are the motors connector or travel stops; see Electric Shift Motor Troubleshooting & Repair Source: by Richard C (Bigric, Money Pit) at
http://www.supermotors.net/clubs/superford/registry/4584/21843
for a big Bronco, but similar
Electric Shift Emergency Shifting; "... I recall in same thread Ricky B wrote this[/url]; I'd thought I'd share some pics for those who may like to know what the t-case 12 volt shift motor does. Or is supposed to do in my case. Just for drill I removed the small motor. You'll only need a 3/8" ratchet wrench and a long 10 mm socket to remove all 6 bolts. Three of them are about 1 1/2" long and goe thru the top right circular head of the motor. The other three bolts are about 3/4" long. One bolts to the bottom flat tang of the motor case itself (ground?) and the other two hold the wire coupler harness in place on the t-case. As I suspected the triangular shaft inside of the t-case was pointing down to indicate 4 High. By merely jiggling the front drive shaft yoke a little bit with one hand, I could very easily move the triangular shaft with my other hand and get it into 2 High..."
Source: by miesk5 at Bronco Zone Forums
&
1356 Electric Shift Emergency Shifting; "...per one of the other threads someone mentioned that the electric 1356's had a square 3/8" hole in the case so it could be shifted manually if the electrics died..."
Source: by Broncobill78 (Dave)
&
"..I'd thought I'd share some pics for those who may like to know what the t-case 12 volt shift motor does. Or is supposed to do in my case. Just for drill I removed the small motor. You'll only need a 3/8" ratchet wrench and a long 10 mm socket to remove all 6 bolts. Three of them are about 1 1/2" long and goe thru the top right circular head of the motor. The other three bolts are about 3/4" long. One bolts to the bottom flat tang of the motor case itself (ground?) and the other two hold the wire coupler harness in place on the t-case. As I suspected the triangular shaft inside of the t-case was pointing down to indicate 4 High. By merely jiggling the front drive shaft yoke a little bit with one hand, I could very easily move the triangular shaft with my other hand and get it into 2 High..."
EDIT #2;
Can anyone confirm that the triangular shaft is the shaft, shift - part number 7N095 - item number 84 as shown 1356 Electric Shift Parts Break Out Diagram w/nomenclature by Steve
the shift motor on the electric version. The 3/4" round hole that I plugged was where the motor mounted and the shift-selector shaft would be inside...I suppose if you could physically turn the shift shaft manually, without having the motor installed, you could shift from one range to another. I think this would be rather hard due to lack of leverage. Randy Z, Casual Mudder), Rest-in-Peace my friend...."
at
http://broncozone.com/topic/12774-bw1356-manual-shift-conversion/?gopid=96107&do=findComment&comment=96107