The O2 sensor reading -26%

Correct, the closed (.6 volt) tolerance is .02 volts, Open (.75 volt) is .05 volts.
If you're doing this with TuneECU and don't have the TPS adjustment guide, PM me and I will send it to you.
 
if u can get .75 volts i would think that would be great i am not going to argue over one hundred of a volt.