May be you guys can help me

[84 400]

okay i have a 84 c10 silverado. It has 400 in it with edlbrok 650 carb and manifold. it also has headers and flowmaster exhaust. Thats all i really know about the motor as it was installed before i bought the truck. I know it by no means a stick motor and wish i knew wat cam and rocker/ heads the builder put in. I know it was a professional job and built down in Georgia. Any ways not that that matters but my ? is is there a D.O.T. approved slick like tire i can run behind this beast?? I really wish i could run white letter Hoosiers but have no idea if they make them DOT approved or not. also i am running rims that are maybe 2 inch wider then stock. any ideas. is ther a fatter tire i could run on a stock rim? Thanks alot
Ian