I installed a GM GEN 3 PCM (0411) along with a 4.8L into my 99 2 Door Tahoe. My fuel gauge was working fine before the swap and now of course it's not reading right. Any insight to what I have to change in the Fuel system tab? I have emailed support but was told "To answer your question I honestly have no idea regaring your issue".
There are some threads on fuel gauge but for camaros.
My PCM does control fuel level.