I wonder about '0411 injector parameters LT1 vs. L31?
Agreed. I would definitely expect to use injector tables that math the type of injector that is installed. The L31 Poppet style injectors are very different from traditional fuel injectors.

IME the stock one ton van injector voltage compensation is incorrect below 10V. If left stock our commercial vans have difficulty starting with a low battery and the exhaust is very rich at idle if the voltage drops. Leaving those tables intact could really mess with traditional injectors.