Ok so I have a bushmaster orc, which is a flat top with a milled low profile gas block. Currently the only sights on this rifle is the eotech 512 I have installed. All I want to do is to have a gunsmith replace the current gas block w/ a standard m16/ar front sight base. Now my gunsmith tells me that this will not be possible without using a raiser on my eotech. I then asked about f-marked fsb's, he still says the eotech dot will be in the middle of the sight base. He then suggested that I get a railed gas block and use flip up sights for front and rear. This completely defeats the purpose as I plan to co witness the front sight at all times and more than likely keep the rear buis up all the time.
Anyways, any thoughts or ideas?