Electrics:

There are some modifications to be done to the electrics. The first job is to convert the Tachometer from 4 cylinders to 8 cylinders, as the V8 will produce twice as many switching signals per engine revolution.
I found a great article on the web, on how to achieve this cheaply and easily.

I will fit a 100k Potentiometer onto the chip and then adjust it to get the correct reading at a given rpm.
The Tacho cover just twists off and 3 screws on the back to release the unit.

 I soldered 2 wires onto the chip, and passed them through the rubber seal, and I will then attach the 100k adjustable potentiometer so I can calibrate the tacho when it is installed.

 Started to make the changes to the wiring loom.
The distributor, coil, electric choke, second cooling fan, and central locking, all have to rewired or modified.

 I decided to upgrade the fuse box and relays, I made a stainless steel bracket to hold the fuse box, which I will now wire up.

This shows the wiring partly done, still a bit to do.

I fitted a second cooling fan to assist in the cooling of the V8, which I will control with an electronic adjustable fan controller. 

After the first engine test, it became apparent that the temperature gauge was reading a bit high. I tested the gauge with a test box I made years ago, and I also tested the temperature sender unit, which appears to be ok, and I monitored the actual engine temperature with a thermometer on my multi meter, I can only conclude that there is a slight incompatability between the MGB gauge and the Rover SD1 sender unit. So I installed a resistor into the circuit to bring the needle down slightly.  I used a 10 ohm resister on the output side on the gauge, I can easily swap it to fine tune later on.

 The next job is to install central and remote locking. I bought a Hawk system, really cheap and quite effective. I marked up the doors and drilled where I thought the motors should go.

 I then bent the actuator rod to line up with the locking rod on the car.

I then wired it all up, with the control box up behind the dash.

Just need to tidy up the wiring and tape it up where it goes through to the doors.