Newbie Questions

[ZACH'S97]

I have a 97 cobra with 75,000 miles on it. The car is in really good shape. The car already has: bassani mid length headers, bassani o/r x-pipe, magnaflow catback, tri-ax shifter, bbk cold air kit, pulleys, steeda lowering springs and strange adjustable struts (rear), maximum motorsports c/c plates-coil overs(325lb springs) -tokico illumina struts, frpp aluminum driveshaft, and 4:10 gears, and a diablo chip dyno tuned at 285 hp. I haven't had the car too long and most of the mods were already done. My next mod has to be tires becasue the nitto drag radials are worn out. This is my first problem area, I have a 10.5 inch cobra r on the rear and the tires are only 275's. I think I need wider, but don't want to have any clearance issues. I am considering both Nitto and M/T drag radials size 315-35-17; will their be any clearance issues on my lowered car? My next question is about performance mods. I am wanting to do a tubular k-member and a-arms. What brands are good besides maximum motorsports because they are to expensive? I have been looking at UPR and PA racing. I want to make sure the k-member will clear the headers. Next question, the car has cheap piggyback style pulleys should I switch to the steeda pulleys? Also I have heard JLT's cold air kit is a lot better than my bbk is this a worth while swap? If so I have a friend who wants to buy my bbk kit. I am not willing to do a gear swap for a bigger gear because I will probably supercharge the car when I am finished with college. Let me know what you guys think I should do. I appreciate the help.