Low budget 5.9 magnum build

I'll give you alittle run down of what I'm doing. Roughly 10 years ago I built an 87 D150 to sled pull, yes 2wd. A few years later I swapped in a 4x4 chassis and pulled in the SB street class with a mild 400. At that time the C.I. rules (412ci) allowed me to use my BB. Since then the class got outta hand with guys running 600-700HP Small blocks and they outlawed the use of a BB. I still have the truck but it saddens me because it's just collecting dust and most of the engine parts got used on my brother's Cordoba. With that being said I opted to jump down to the SB showroom class. I have a magnum block, SCAT 9000 cast crank (3.58), SCAT forged I beam rods, and a set of used forged flattop pistons with valve reliefs(don't know the make). I want to be able to drive the truck to and from the pulls. Rules for that class allow 3 bolt ons (headers, Holley carb, and intake) they consider a lopey idle an add on. I figure if I go with a bigger cam, intake, and headers that would give me my 3 add ons. I have a Carter AFB but being they were a Mopar carb before edelbrock they can't ***** about that. I'm trying to get as close to 400-450HP at the lowest possible cost. I'm not afraid to get out the die grinder to help my goals. I'm all about "Made in USA" but cheap is not always made in USA. With that in mind Im looking for opinions on intakes and heads for the magnum. I was looking at the Promaxx replacements and others. Also was checking out the Chinese Air gap. Any opinions are appreciated!