Toyota Pickup/4Runner (1979-1995 4cyl Gear Drive Application)
1) Remove T-case from truck. See repair manual. Shift T-case into 4wd.
2) Remove shifter base assembly (top shift, 79-83 & 85 -88 EFI) or block off plate (forward shift, 84-88 carb, 89-95 EFI, 86-87 Turbo).
3) Remove Driver side detent bolt, using a 6mm Allen head wrench (see #1 in picture below). Be careful not to loose the detent spring and ball. Tilt case with plug facing upward. Remove detent spring and ball. Tilt T-case on its side or use a magnet.
4) Drive roll pin out of high/low shift fork (see #2 in above picture). Use a 3/16 roll pin punch to remove the pin. Place a magnet pen under the fork to catch the roll pin. If no magnetic pen is available you can let the pin fall inside and remove it by turning to T-case up side down and rotating input shaft. Shaking the case as you rotate the input can help stubborn pins come out.
5) Slide driver side shift rail out. You can grab the rail with a pair off pliers or stick a 3/16 punch in the rail and slide it out until you can grab it with pliers.
6) Once the rail is out, remove the interlock pin. To remove pin use a magnetic pin, tilt case on it side (with a little force) or use compressed air in the passenger side rail slot (see #3 in above picture). The pin will fall out of the same hole the detent bolt was in.
7) With the interlock pin removed you can now reassemble in reverse order.
8) Lift the shift fork and slide the shift rail back in place. Drive the roll pin back in place. Be sure the side with 3 notches shaft faces out.
9) Install the detent ball and spring. Install detent bolt. Use high tack or ultra gray silicone on threads.
10) Install T-case into truck. See repair manual.
11) Install twin stick shifter. Use ultra gray silicone and don't forget the metal plate. line up the shifters tips with the fork and shift block (top shift only) or shift rail ends (forward shift only).