Thank you, my dad built it out of 3 different trucks, the chassis and running gear are out of a 2500 and the body is a 1500, the bed is off of the third truck. He went through everything as he was building it so it's a very nice, solid truck.

 

Pull the 37s off and put some 225/75 R16s on and go for a test drive. That will show you about what the 4.88s would do. You'll probably spin the tires at the first couple of stop signs.

 

4.88s Would do both, although, I think for top speed, it really wouldn't be that much of an issue. It's a truck, it is not a back street weapon. Driving it as such pretty much ensures that you, and possibly others, will end up dead. Just don't do it.