I posted previously I had bought a donor shell to re-house the innards of one key, and as I now had a second key with the rubber buttons caved in and a shell that was damaged / scuffed but with reasonable button's I have just rebuilt a perfectly working second key now from the two originals and am well chuffed.

Sorry no pics but it is quite an easy one.

I flicked out the blade then split the shell apart at the opening it is very tight to prise apart at the metal keyfob end but once you do that it's easy and comes apart.

Take care with the small loose battery clip and keep it safe, remove the spring button and blade and take the time to scrub the muck out the blade.

Check the microswitches mine were all in perfect shape and the problem was the rubber push shell had slid off the switch and hence didn't work!

I used a small brush and scrubbed the entire assembly clean and dried it with a tissue then re assembled it all.

I was tempted to have a flick retract on the blade but just went for the regular flick to extend.

I went out and tested it and BINGO! one refurbed and working key.