yes, stock ecu - dynatek - PC5 - injectors. Doesn't matter which injector. The AutoTune has a small cable to connect it to the PC5. You do have the O2 sensor connected to the AutoTune right? You can connect a laptop to the PC5 and watch it do the work as it tunes. You will have to download map to see the adjustments it just made, then accept the changes, then send map to load the new fuel mapping back to the PC5. It is easy.
Not sure on the 2100, other than it sounds lean. Get a laptop on it to see what your AFRs read.