Wideband

The 38* locked timing may be a problem in two ways.
One - timing and fueling go hand in hand. I know, less of an issue here with a manual transmission, rpms will be up by the time you fully load the engine.
Two - The AFR reading is an interpraton of the wideband's reaction to the oxygen. Assumptions are made about the combustion process. When the fuel - air combusts differently than assumed, the oxygen left over is different. When this happens, you get false reading. I'm not saying it will happen, but beware it is more than possible. If readings don't make sense, this is probably why.