Removing the front sight from an A2 rifle is relatively easy, just get a punch and a hammer and knock the pins out. You will need a new crush washer for the flash hider if your rifle has it to replace the one thats on it now when you remove the flash hider. You can get a low profile gas block for around $20 and most are just set screw installation. When you pull the A2 front sight off, knock out the very small pin that holds the gas tube in place and reinstall in your new gas block. You tube will make it easy to understand and its not a hard job if you are comfortable doing it. If you were local I would do it for you.
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