anyone have a definitive list of the open style filters available for the 1300? I understand it's fairly easy to build one myself, but also see that the mass produced ones seem to have some features(crankcase drip lip, flush fit, etc) that i much prefer. Already attempted to talk to the Ashford guy, seems he's not answering his site email, don't really like the arlen ness one, although at the moment it seems the only option. Thnks guys.