go to KatRiders.com and sign up. FYI, your Kat 600 was engineered to handle as-is with the 150 tire on. In order to put on a 190 you will have to modify the swingarm, get a new rim and all for the purpose of making your bikes handling worse than it was. Ok, it'll look a little better if it's done right but that's about it.
As for the solo cowl, there is a guy on katriders that makes them. Be prepared to pay though, if he is even still making them. You may luck out and find someone who's looking to sell.
Good luck and if you do join up, check out Cyberpoet's thread on tire sizes.
hey everybody thanks for taking the time to check out my post, anyways im currently working on my buddy's 1988 katana 600, he is trying to find out what is the widest rear tire that will fit with out haveing to mod anything. the bike calls for 140-80-17 i think. i did the whole measuring the...