You will be fine the 7/8" is a starting piont for that particuler bow .
Where your center shot setting that you have at this point is derived from your form,and your shooting style.
Not everyone can use the recomended center for this reason.
All it is,is a starting point .it is the center of riser in relationship to the string.
The center shot for my Buckmaster 2000 is 13/16" and my actual setup for centershot is 7/8" for me.
Have fun and Keep practicing..