Many thanks gents.
I live in Guernsey (off the coast of France) and getting some parts from the UK is difficult and I may have to get them shipped from the States.
Sonnds like removing the cats may be a good idea and the downpipes look very good. Either way, the intention is to scare the elderly, young children and of course my pets so I am please to have a solution
.
Cheers!
Dave