This will give you an idea of what is involved;
- Install a clutch pedal assembly
- Change the brake pedal
- Install a clutch master cylinder
- Install hydraulic lines that tie into the brake system (the brake and clutch share hydraulic fluid)
- Bleed brakes/clutch system
- Install manual engine harness
- Remove all of the Tip wiring/relays/controller
- Get the remaining electrics/wiring to work
- Install a manual car gauge cluster (no gear indicator lights)
- Re-program the gauge cluster for mileage
- Re-program ECU
- Install flywheel, clutch, pressure plate
- Install 5-speed transmission
I am sure that I forgot a few things, but you get the idea.
Its a pretty big job and obviously not economically worth the effort.