So what's more important, making the bottom of it flush with the receiver or keeping the left side even with the bolt rail?

I watched a YT vid that said to make it flush with the receiver by removing metal, but in trying to do so it looks like the rail and bullet guide are no longer even and the guide sits down a bit.

Wondering if I should buy a new guide.

Below is what it looks like. When I got it it was pretty much flush or slightly high, but there was a decent gap at the base. After removing most of it I noticed the guide/rail were no longer flush.

Attached File


Also, would anyone know what purpose the taller guides have?

I noticed there are two different types available to buy.