You don't. The faulty line must be replaced.
Freon is added to the lower pressure line port. It is the only port a refill kit will fit. I suggest taking it to a shop that does A/C repair if you do not know that already.
It's in the low pressure line running along the passenger side of the engine compartment. If there is a connection there with a nut, it's inside the tube there. If the line has no connection, it is crimped in and that section has to be cut out and replaced with a repair kit, or a new line installed.
The Villager does not have a test port. You need to tee into the line at the fuel filter.
5/16" supply 1/4" return.
Under the hood, right side, in low pressure line.
The Villager does not have a test port, you need to tee into the line near the fuel filter to test pressure.
If you mean the orifice tube, it is in the low pressure line. If there is a hex nut in the line, you can separate the two parts and remove the orifice tube. If there is no nut, just a crimp, the line must be cut and a repair kit installed to contain the new orifice tube.
I've never seen them separate. Maybe you have a slip in the line somewhere.
It's in the air conditioning low pressure line, basically running along the front part of the engine near the pulleys. There are two types, one kind has a screw connection that you can open to retrieve it, and one kind is embedded in the line and has to be cut out and replaced with a repair kit or a new line assembly.
You'll need to install a tee into the line by the fuel filter to check it, there is no shrader valve.
belt it self has timing dots on it, line it up with cam dots and crank dot.
If you mean the fuel pressure regulator, it's on the end of the fuel rail near where the fuel line attaches.