id say try pm'ing people like beastlywarrior228, or sidewayz, they are flat track racers from what i know, and its possible they could give you a rough estimite on what you will want based on your budget. heres what i think you should get... this is just for a budget.. flip your front and rear rims, put flush mount valve stems ont he front, get lowering blocks on the front, the one of those lowering pieces for the rear linkage, adn of course tires, but fo r those talk to people who race flat track, then your gonna need different gearing for those tires, and if your looking to do some basic engine mods, id say put a mild cam in it with a high comp piston, and then after you get that, youm might wanna look into a sway bar.
and the tires will probably be the most $$$