yo ROGMIT,
Replace TC seals, gaskets...and may as well do engine. rear main seal due to age issues.
and,
Transfer Case Fluid Level High & Low Transmission Fluid Level &/or Shift &/or Engagement Concerns TSB 97-12-13 for 87-96 Bronco & many others; "...transmission may have low fluid level and/or may have either a shift concern and/or an engagement concern. This may be caused by transmission fluid leaking from the transmission into the transfer case through the transfer case input seal. Replace the transfer case input seal..." read more Source: by Ford via thedieselstop.com
www.thedieselstop.com/faq/9497faq/tsb/tsb/files/971213.pdf
1356 Manual Shift Parts Break-Out Diagram w/nomenclature
Source: by Steve
http://www.supermotors.net/clubs/superford/registry/media/249572
1356 Electric Shift Parts Break-Out Diagram w/nomenclature
Source: by Steve
http://www.supermotors.net/clubs/superford/vehicles/registry/media/469461
BW 1356 Gasket & Seal Kit Ford Bronco http://broncograveyard.com/bronco/i-31642-bw-1356-gasket-seal-kit-ford-bronco.html 
# 31642
New
1980-96 Ford Bronco
Borg-Warner 1356
Gasket and Seal Kit
Price: $30.00
KIT INCLUDES:
-Input seal
-Front output seal
-Rear output seal
-Output seal
-Adapter gasket
-PTO gasket
-Spline washer (2)
-O-ring
Check motor & TC mounts
1993 Bronco/Econoline/F-Series Workshop Manual by Ford - similar to your year
https://www.motorcraftservice.com/pubs/content/~WSPM/~MUS~LEN/21/SPMLEFT.HTM
Look through it; such as for example;
Section 07-07A: Transfer Case, Electronic Shift
1993 Bronco/Econoline/F-Series Workshop Manual
REMOVAL AND INSTALLATION
Rear Or Front Output Shaft Oil Seals
Removal
- Raise the vehicle on a hoist and position suitable safety stands under vehicle.
- Remove the rear or front driveshaft from the transfer case output shaft yokes. Wire the driveshaft(s) out of the way.
- Remove the output shaft yoke by removing the 30mm locknut, steel washer and rubber seal from the rear or front output shaft and remove the yokes.
- Remove the oil seal from the front or rear output housing bore with Seal Remover T74P-77248-A and Impact Slide Hammer T50T-100-A.
Installation
- Make sure the front or rear output shaft output housing bores and faces are free from nicks and burrs. Coat the oil seals with Premium Long-Life Grease XG-1-C or -K (ESA-M1C175- B) or automatic transmission fluid. Position the oil seal into the front or rear output housing bore. Position the oil seal into the front or rear output housing bore, making sure that the oil seal is not cocked in the bore. Drive the oil seal into the bore with Output Shaft Seal Installer T83T-7065-B and Drive Handle T80T-4000-W.
- Install the yoke, rubber seal, steel washer and locknut on the front or rear output shaft. Tighten the locknut to 203-244 Nm (150-180 ft-lb) front; 162-203 Nm (120-150 ft-lb) rear.
- Connect the front or rear driveshaft to the transfer case output shaft yokes. Tighten front driveshaft-to-transfer case yoke to 11-20 Nm (8-15 ft-lb), and Bronco rear circular ****** bolts to 28-33 Nm (20-28 ft-lb). NOTE: F-Series vehicles use a slip-yoke at the rear output of transfer case.
- Remove safety stands and lower the vehicle from the hoist.
Section 07-00: Transmission, Manual, General
1993 Bronco/Econoline/F-Series Workshop Manual
CLEANING AND INSPECTION
Transmission
Cleaning
After the transmission has been disassembled, soak the parts except the bearings, in a cleaning solvent until all the old lubricant is dissolved or loosened. Brush or scrape all foreign matter from the parts. Be careful not to damage any of the parts with the scraper.
An excessive amount of foreign material usually results from a bearing failure, gear seizure, tooth breakage, extreme synchronizer wear, or clashing gears.
In such cases, the input and output shaft bearings should be carefully inspected and replaced if necessary. Since countershaft bearings, output shaft pilot bearings, and reverse idler bearings are not so susceptible to damage from foreign material in the lubricant, they need not be replaced if they seem satisfactory.
Wipe the parts or blow compressed air on them until they are thoroughly dry.
To clean the bearings, rotate them in clean solvent until all lubricant is removed. Hold the bearing assembly to prevent it from rotating and dry it with compressed air.
When the bearings are dry, lubricate them thoroughly with transmission lubricant and cover them with a clean, lint-free cloth until ready for use.
Inspection
Inspect all transmission parts before reassembly to determine if they should be replaced.