Looking at Eric's pictures I decided to try and cheat.
With the door skin attached with a couple of self tappers I drilled through the GRP and steel skin together. I simply guessed at the centre of the hole using the mark on the door. The mark on the door is just where Chris has obviously filled in the hole where he had fitted the door handle and roughly filled it.
I then pushed the drill bit had and the door popped open
I did the same on the passenger door but this time it didn't pop open, never mind.
I then removed the skin and used a 40mm hole saw.
You can see where the drill bit hit the opening bar, you just push the bar to open the door. I now just have to fit a small metal plate as per Eric's guide.
If you were to guess the centre of the hole on the GRP skin and there lower it 5mm I think it may well hit the centre of the door push and you might get away without fitting the plate.
When enlarging the hole with the hole saw you will find there are two layers of metal at the top, drill and remove both, the second layer is something to do with the lock and can be removed.
I intend to glue a larger diameter slice of plastic pipe above the new hole, this is to deflect any water running down the original door skin and entering the hole.
I was quite surprised at how much water had collected in the bottom of the new GRP skin, lots of drainage holes will be needed.
Use the small drill hole in the outer GRP skin as the point where the door handle push goes through. Use the gasket supplied with the door handle as a template.
On my door handles I cut off the door locking lever, it is not needed and means you can keep the hole in the door smaller. You can dismantle the handle but I cut it off with tin snips, that way I did not have to remove the push on fixing, they never tighten up as well when used again.
For clarification, when you lock or unlock the car using the remote key fob, when locked the new mini door handle will not open the door, use the fob to open and the mini handle will open the door so there is no need to do any extra work on the locks. If your remote fob doesn't work I would suggest you get it working first. If the remote locking breaks after you have fitted the new door skins you are *ucked! Most likely cause for failure is a flat battery so I intend to leave the boot with a manual key lock so I can get to the battery. I also need to try and fit an emergency release cable so I can hopefully open the door in case the remote locking packs up completely, job for a later day.