OK, so which bits do we have to source ourselves, and which bits are we signing up to Doug for?
As far as I can tell it's get everything but the modded bolts yourself

(halfords bits - pipe, elbows, jubilees - are easy, then a cheap cone filter, and a scrap golf intake...).
Unless we make it a group buy on bolts and filters, and get in contact with some large breakers somewhere to cache intakes for us and flog the pile cheaper as they're a guaranteed sale?
And remind me again - any chance of even a slight power boost, or is it just the nicer sound and smoother airflow/response?

(suppose the cat really has to come off first)