Welcome to CompD!
Are you still planning to drive it regularly on the street, or will it be a dedicated puller? Will you also drag race it at times? I've never pulled, but have been to many pulls. I've been drag racing for a while though. Do you read Diesel Power magazine? Some interesting info in their Diesel Power Challenge (where trucks are scored in several categories including pulling and drag racing).
I have been considering building a multi-purpose truck (which would occasionally hook to a sled), and I'm still torn about what I would build. Originally it was going to be a 1998 QC/LB 12V Dodge, wanting the simplicity of the 12V. I figured I could change out plates and even injectors depending on what I was doing with it (and run a charger combo that works well with towing). However, it is sure nice to be able to quickly swap tunes on an electronically-fueled truck, to allow it some decent street manners and towing capability. I have seen some Chevy trucks lately that have done very well as multi-purpose trucks. In other words, if it is more of a dedicated pulling truck then I would get a 12V Dodge, otherwise I'd go with a Duramax.