Step 1
First, separate the upper and lower hull, next, remove all the electronics/mechanisms except the main gearboxes.
Note that once you can access the driver’s hatch from the inside, the locking mechanism can be operated, and the hatch opened, with nice details on the hatch underside.
Also the ‘plug’ located on the forward underside is the crystal holder, pull that straight outwards.

Step 2
The existing turret rotation gearbox and turret traverse ring will also be kept, and can be run by a Tamiya DMD control unit, the only catch is, the turret is ‘locked down’ to the upper hull by the turret ring and won’t be easily removable like the Tamiya turret rotation system which facilitates easy access for changing batteries/maintenance.
Here, the electronics that won’t be needed have been removed, and the battery compartment has been cut out to make room for all the Tamiya gear to be installed.
Now you can put all this stuff, including the radio into your spares box.

Step 3
Here is a photo of the layout I used for the Tamiya components in the lower hull. I removed all the plastic upper/lower hull joiners except for the one over the gearbox and the two at the front of the tank. I then filled the holes and used a piece of plastic card to make a smooth base for the electronics to sit on. A mate of mine, JC from Canada used a different method in installing the DMD and MF units on their side, which enabled him to use the existing battery ‘door’ underneath to place/remove the battery. These electronics are all from a full function Tamiya Sherman RC tank

Step 4
This photo shows the positioning of the TBU receiver. You need to cut the hatch out, you can drill a small hole, then insert a piece of cotton and run it back and forth vigorously, friction will melt a very thin cut ;(thanks to John Price for the idea) Once you have cut out the hatch, position the TBU base so that the hatch sits on it when replaced. To get it at the right level, I used a PVC hose clamp to hold the base, and glued the clamp into position.