[gcrank1]

If it is pretty much a 'target gun' and a min. 1" tube scope you dont really need to be seeing all the way out to the outer edges of the objective lens, ya aim and shoot with the center. The bigger obj. still 'gathers the light', etc.
Ive mounted a few scopes farther forward than 'normal' on purpose to no ill effect. It is wayyy good for hard kickers so you dont get slammed by the ocular bell and also good for prone. It is far easier to crowd the comb forward than to pull your head back too.

 

[gcrank1]

Just a thought....are you sure that is the right EGW rail for that rifle?

 

[gcrank1]

A lot of set screws have a fairly sharp edged 'cup' on the end, waayyy easy to mar up a contact point!
Grind/file it off smooth.
Btw, I used a cut down 22 case for a similar application; seemed appropriate

 

[gcrank1]

Thus mounted on the barrel taper it must be accounted for from a true bull (constant) dia. barrel as it gives some 'extra elevation' based upon the angle created to the bore-line.
The scope, will 'point down', thus elevating the muzzle and shooting a higher trajectory (often needed for the now popular 'long range' shooting).
The -0- moa cantilever mounts duplicate what typical dual, or one piece scope bases do, IF mounted on a section of parallel to the bore barrel (often a tapered barrel will have a 'bull' dia. section just ahead of the receiver before the taper begins.
The +/- moa point the rail itself up or down so accommodate the range of the scope elev. adjustments for closer or farther away/special circumstances.
It is mathematical to great degree once you have defined your preferred distance and proven your point of impact.

 

[gcrank1]

Get some risers for the sights?