Hi all.  I am deciding on optics and sling for a project.  The rifle is a carbine length SP1 conversion.  See picture.



I am considering two options.

Option 1)  EOTech.  I am considering the EOTech 552 Rev E with the new battery option.  I would also install an ARMs #40 BUIS.  I would like these to co-witness.   I don't know what if any mount I need to get with the EOTech as it "seems" to mount directly to a Weaver style rail as is.  

Questions -

a)  Do I need an additional mount for the EOTech?  If so, which one.

b)  Will the ARMs 40 and EOTech cowitness and do I need to change the front sight post?

Option 2)  Aimpoint.  I am considering an Aimpoint ML2 with 4 MOA dot and ARMs #40 BUIS.  Pretty much want the same as above with cowitness etc.

Questions -

a)   Which mount for the Aimpoint for cowitness (I prefer ARMs and probably will want the 22M68).   Does this cowitness?

I also want a simple usable sling.  Nothing complicated, just holds the rifle in  a ready position.  Suggestions?

Also, best advice on purchasing this stuff.  

what is wrong with the sight you hsve on it now??  If you do not want it I maybe want to buy it from from you.  I used both sights and like the EOtech over the Aimpoint.  The only thing was a shot aimpoint on a M-4 and the Eotech off of a mp5.

With regard to the EOtech, it has a built in mount that puts it at the perfect height to cowitness with an ARMS40.  I have this combo on my carbine and if I put my nose to the charging handle I'm looking though the ARMS40 and the EOtech's 1 MOA center dot is right on top of the front sight post - perfect cowitness.