Looking at doing some major surgery to mine as well. Ironically, I've been on here defending this platform in the past, because of it's reliability and accuracy. Then, basically overnight, I couldn't hit a Boeing 747 at 20 yds.
All of a sudden, there just wasn't enough adjustments for windage, regardless of the distance. All I can assume is, that the plastic sometimes moves around the actual firearm.
When you might be shooting at something with a heartbeat (i.e. a Seagull), you owe it to them to hit them in the right place the 1st f*c*ing time.
It was rock solid until it reached about 500 rounds. Then, it went 'rogue' and now I wouldn't shoot it at anything that wasn't paper-backed.
Time permitting, I'll take some power tools to it, lock down the plastic and attach 3rd party optics. If you don't have the time, don't buy this gun.