need info for towing lq4 build up or stroker build.

I have a 1999 chevy 2500 sliverado 2wd that i bought new in 1999. i crashed it a few years ago and swapped out the 99 motor for a new 05 as long as the front clip was off. the truck has 250,000 miles on it now.It always pulled my 28' race car trailer quite well with both motors. In july 2008 i bought a very clean 2000 chevy 2500 suburban 2wd with 106,000 miles to use for towing the race car trailer. it now has 160,000 miles. both trucks have the same 6.0 motor,l80e trans,3.73 gear,tires,and curb weight. the suburban is in way the same when pulling the trailer. i am looking to do something to make more power for towing. I need it to be a good daily driver and run for a long time like a stock motor will. im looking for some real world proven combo's that work and last for 100,000 plus miles.
i drag race and have built sbc,bbc and hemi's that have ran on gas,alky and nitro. i have built a stump puller 406 sbc for my 1989 chevy 2500 4x4 that was very strong! i have changed the 6.0 in the 1999 pickup but that all i have done with the 6.0's. i'm not looking to get nut$ just make power for towing.
thanks for any help or leads to what im looking for on this build.

Why not do both? Do a 408 stroker build on the LQ4. Get the heads ported, then get a decent cam (talk to the cam seller to get a good specific cam for your build). You'll have plenty of gut wrenching torque to deal tow what ever you want and to get you off the line when you want to play a little. Just a thought.

A 408 with high compression = perfect for what you're looking for. Flat tops and worked 243s sound right up your alley. Just finding a cam that offers the power down low without a stall is going to be the kicker.