|can be installed into it. Try PB Blaster. If you can't remove it buy a new one. Use anti sieze on all the threads to prevent future binding.
For a vacuum port to use for the gage connection get a small tee at Pep Boys and insert it at the vacuum line for the fuel pressure regulator in the picture above that connects to the passanger side of the balance tube. This way you can do the test and still have the regulator connected.
The vacuum readings I provided are not spec but are typical and expected for NA engines in good shape. Engines with really modded cams with lots of intake and exhaust valve timing overlap will produce lower vacuum readings but that is not typical for stockers. For all the cars I have owned thru the years the readings have been right in that range. What is very important other than high readings is a steady needle.
ZUL8TR in Orlando,FL