Timing dial indicator

[CLiberty]

I picked up a Central Tool metric dial indicator, but i don`t have the extension needed to get inside the timing port on the back side of the pump. I can get a generic 4/48 thread extension but i need to know how long it has to be. They are offered in 1/2in increments up to 3in and then in 4 and 6inch. I`d like to ck my timing the "proper" way, esp since i scored the dial indicator for free#ad

 

[Paychk]

The boby part of mine is 3 1/4" long, with the threaded tip included it is 3 3/4" long. I would say get the 4" model.

 

[CLiberty]

Thanks a bunch!!