I originally posted this over in the V8 Gen 5 forum because they get way more traffic than here, but I actually developed this app with my LGX V6 Camaro. It should be applicable to any GM that has a driver demand table with rows referenced as accelerator pedal position and columns referenced by vehicle speed.
Check it out: Driver-Demand-Editor-new-tool-for-tuning-DBW-throttle-mapping
Cheers,