360 Balancing

we have a 360 with sealed power hypertech pistons and stock rods. Have a set of forged icons we would like to use.We would also like to use some scat I beam rods. The pistons are 90 grams lighter and the rods are about 150 grams lighter. My question would be about balancing the cheapest way possible. We have the b&m flex plate and external balancer. Dont wont to have to spend a ton of money on mallary metal.