Plug Screw for Master Brake Cylinder

[big_dawg]

I'm plugging my rear brake line from the master brake cylinder for a short period of time.

This is a link to the brake cylinder I have.
https://www.oreillyauto.com/detail/.../5517/automotive-truck-1990-ford-ranger?pos=0

Any links to a screw that will work? Already tried one bolt and it didn't work so figured I would get some extra insight!
Also, am I plugging port 1 or port 2?

 

[Uncle Gump]

I'll be the first...

Why on earth would you do this?

Fix what's broken and make yourself and anyone you encounter on the road safer.