When you update your SCT Tuner, you should not lose your stock tune. Anyway mine doesn't. Follow the instructions for updating Firmware etc. on SCT website where you will get the updates.
So no one uses stage 2 anymore? Don't I have to run 93 octane to run stage 4? The highest we have is 92 octane and luckily that's just a couple of blocks from me. Can I run stage 4 with 92?