Rotary Table Mounting Method

[Toolmaker51]

An alternate would be mounting to a flat plate, to occupy less real estate than an angle plate, or accommodate longer parts. It is common to not index or mill parallel to the X-axis and a plate would allow that too.
We normally remove fixture keys for that reason, indicating the part for desired alignment. It also saves the surface from unintended marring; keys on larger tools are hardened.