When you buy new parts, the least you can do it expect them to work… However, in testing some of the electrical components that I have purchased ready for fitting, I kept on blowing fuses when trying to get the wiper mechanism to work.
Having ordered another wiper switch, thinking it might be that, I decided that there was no alternative to taking the wiper mechanism apart.
Having done a lot of head-scratching and Googling, I concluded that there was no way for the mechanism to work the way in which it was shipped and that it would always short when put into park (as the negative and live were made to contact on the cam at in this position).
Some more head-scratching and drawing up different logical and physical wiring diagrams, I re-wired the components. In essence swapping spades 2 & 3 over and re-soldering one of the capacitors and motor from spade 3 to spade 2.
This did the trick and the mechanism now finds park correctly and has stopped blowing fuses ever time it is used.