Your guru needs to go back up the mountain he came from, and meditate a bit more. Replacing with a higher sight will only make POI lower!
If you don't want to switch front sights to a LOWER one, you can file the front post down a little at a time, and test. Once you're hitting where you want, touch up the sight with cold blue.
If you don't want to switch front sights to a LOWER one, you can file the front post down a little at a time, and test. Once you're hitting where you want, touch up the sight with cold blue.