One of the signature limitations of the Mark 2 wiring is that there are only two fuses to protect the whole system. Not only is this a very poor protection scheme but it also makes trouble shooting very hard indeed,

I fitted a standard new wiring harness to my car and added a multiple fuse block. This is very easy since the power wires all converge at the original fuse holder and it is a simple matter to spread them out individually so that each one has its own fuse.

Attached is a copy of my supplemental manual that shows some of the details. Although I have done many other modifications to the wiring at least you can see the multiple fuse approach I took.

Also attached is the maker data sheet for the fuse holder.

 

Check-out Mobeck Tekniske on you tube. He does harnesses I believe.