Exhaust system design help.

[KD4UPL]

I'm hoping to finally get my '69 c10 shorted on the road. The first thing it needs is an exhaust system. It doesn't have much of one and what is there is totally rusted.
I wanted to add headers but the manifolds are in good shape and I hate to spend the money on something that doesn't need replacing. The engine is a 307, the trans is a TH-400.
I would like to keep true duals. Is an "X" or "H" pipe required. Is there a difference?
I would like some kind of mufflers; I don't want the truck real loud but I want it to sound good. Would Cherry Bombs or glass packs be a good choice?
I was thinking of just turning each tail pipe out in front of the rear wheels. This would save bending it up and over the rear axle. Does anyone see a problem with this plan. The rear end is leaf springs for some reason, if that matters. I don't know if it's factory or not. Not much of the truck is.