All engine fasteners from APT are manufactured by ARP , the most respected and well known name for performance fasteners. Here is what the studs look like when installed for a Sprite or Midget, which is fine. For a Mini this setup needs to be changed, as outlined in the text . Here, you can see how little room there is. All checking is done without gaskets between the flange faces.
First step is to remove the locating rings.
Tap all holes right to the bottom.