What kind of project are you going with; pump, spimmy/ fasor?
I assume you mean the standard front block threads. Some use a cap plug.
If your looking for an easy LPR setup use a front block from a timmy.
As far as what threads work, There was a trilogy pump kit from PMP that fit spyders. If that helps maybe a trilogy LPR could screw right in?
something something something
I'm all out of ideas again and this text is so plain.
I'm still not sure how I feel about this new look.