I did this job a couple of weeks ago

The wiper mech is the easy part, the scuttle is the ball-ache job!
Its worth being aware that the scuttle comes off square (straight away) from the glass, ie doesn't pull down towards the engine bay.
The scuttle clips into a narrow plastic strip
fixed across the bottom edge of the screen. I very carefully used a flat blade screw driver to lever the scuttle off against this strip. Once it started to go I ran my finger along under scuttle and it popped off no probs.
Refitting: Go to town cleaning the muck out the strip and soak it in WD40, should go back on OK.
After all that I managed to break it by dropping it putting it back on!