Photos and Text by Thomas Gosser
Place loco on its top or side to access coupler boxes.
Remove coupler boxes using small phillips screwdriver. Turn loco right side up.
Gently slip loco shell straight up and off of chassis. Watch for wires attached to shell.
Remove jumper plug from harness attached to circuit board.
Plug T1 decoder into harness. Tape down if needed.
Replace loco shell gently.
Place loco on test track try out installation.
If everything works you may now reinstall the couplers/boxes.