TPS code. What should I do?

Ok, I got the P0120 code (again!). I already tried to adjust the tps a while ago by the Chiltons method and maybe this too http://www.plymouthlaser.com/tps.htm I don't remember. Basically I ended up turning the tps a couple mm's to the left, almost as far as it can go. It seemed like I fixed it because the CEL hasn't come back since then. But when I went WOT it came back again. That's exactly how it happened last time too, which is kinda weird. So I was reading this thread http://www.dsmtuners.com/forums/showthread.php?t=13183&page=2&pp=25&highlight=p0120 And 'steve' said this:

"On a 2G the TPS is adjusted by where the internal IPS opens and closes not by any specific TPS voltage.

If you search you find a post where I explain why you can't set the TPS by resistance as suggested by the aftermarket manuals and the VFAQ site."

So Chiltons is wrong? So how do you adjust the 2g tps or tell if it's working properly?