71 c10 6.0 ls swap tips and suggestions?????

[Reed123]

Hey guys, new to the block and was wondering if yall had any tips or suggestions. This is my first true build so im curious what you have done that may help me.
My truck is a '71 chevy swb
i have a 2006 6.0 ls with a 4l80 trans that i robbed out of a perfectly good chevy 2500!! (i did save the wiring harness and throttle pedal)
motor and trans have already been installed.
Truck is lowered 4 1/2 in the front and 5 in the rear with springs and spindles. May bag it in the future but went this route for now.
Paint is original with no intentions on painting it.
Frame has been sandblasted, all new bushings, shocks, brakes, brake lines and painted with dupli color rust barrier.
The truck was origially 3-n-the tree.

Questions:
How and where i should install the shifter for the 4l80 trans?
Is it possible to use the original guage cluster with the ls wiring harness?
What wheel tire combo should i use?? Id like to have the tires barely tucked up in the fender wells, but i do not want to c-notch the frame or tub the bed.