You're not going to want to run any sort of upgraded 9.8" garbage at the Dragon. Talk about brake fade city. What wheels are you trying to put brakes under? I just pieced together my second set of 26mm Z brakes and they fit under my 93 SE wheels just great.

I'm not familiar with the J30 upgrade, but I'm assuming that it's some sort of 2-pot caliper on an 11" rotor. If you can score that for cheap then I'd go for it. Definitly go for the good fluid and lines.