Thanks for the advice everyone. I just finished two add-a-circuit installs on my 2010 Mini Clubman S (radar detector and dash cam) and it went very smooth. I did not realize the 99 Rover Mini has ATC fuses, the bigger ones, so I have some add-a-circuit fuses on order and will have to tackle another weekend. Seems pretty easy though and I think I'll tap into C4 10amp (radio, brake test switch, alarm, direction indicators, clock). 

              just run a wire from the pos. side of the battery, inline fuse holder, to the power point.   the fuse size is determined of the load you will be putting on the circuit...

        make sure you cover and route the new wire out of any harms ways...

                  i can tell ya how to make it a switched wire but i like my power points hot at all times....

             don't start messing around and or adding wires to the fuse block....your unsure with just adding a power point let alone wiring your fuse block.......KISS rule....keep it simple silly...

                        solder and heat shrink all connections....take your time and do wiring neatly...secure the new wire in it's Shielded Convoluted covering along an existing wiring loom.....justt do a damm tidy job on it all right...

                  ya got it now..????

A modern mini has alot of options.

Attached is the fuse diagram. You can tap into one of those or use an unused location.

//www.tmsmini.com/cooper/pdf/fuses.pdf

Have you completed this yet JustD?

I want to do the same thing today (off to the auto store in 2 hours) ...

B. 

HI

Ok, I'm pretty handy with home electronics but not a clue when it comes to cars... I'm trying not to torch the new car (1999 MPI Mini) but want to add an accessory (née "cigarette lighter") outlet. I was planning on using one of the empty slots in the fuse box inside the car. 

I guess I was expecting a fuse box like in a house, where one side is "hot" and all you have to do is wire to the cold side and then put a fuse in. Not so...

• How do I add a switched (only hot when the car is on) line to the fuse box?
• How do I actually add a new fuse? There are two red plastic strips running down the back of the box which seem to hold the connectors in but I can't see how to slide them out?

Thanks.

-David