Here I'm going to show you how to modify a standard "dead head" Holley reg to a full bypass type.

Here is the stock regulator in pieces, you can see how small the stock feed hole is and why these things are capped to around 450HP.
Here is the retainer, spring and ball valve. The part on the far right is the seat for the ball and this can easily be removed from the housing with a small drift or a bolt used as a drift (punch). Remove them and throw them away.
Here is the standard diaphragm....