Howdy. Welcome to the FTF community.
Midwest website says the FFG is to be used on a gas block that is lower than the rail on the upper, such as your Oracle. You can raise and lower the post on the front sight, best to use a specific tool for this. Front sight tools are not terribly expensive.
The rear sight is windage adjustable only.
Just do not mount a plastic/polymer sight directly on the gas block, it could melt if enough rounds were fired. Gas blocks get very hot, quickly.
Please stop by the Introduction section and let everyone know you are hear.