I assume you mean the 3.9L because the 4.3L is a Chevrolet engine. The 3.9L has a capacity of 4.0 qts. If you ever have a service place do an oil change, double check their work before you leave because they like to overfill it.
4L60/E l
.043
.43L. 1000ml=1L
43L of 18-k gold
Yes it will bolt right up to it.
There is one before and one after the catalytic converter.
The fuel lines around the filter; you will need an adapter.
There is no adjustment required, but you can clean it with a carb cleaner.
Use an exhaust made for an LT1 engine the blocks are identical it is the insides that is different. Will bolt right on.
Don't know what year you have but some sensors are temperature sensitive and you should run a 195 degree thermostat.
It should be on the front of the intake manifold directly above and behind the water pump.
sounds like a vacuum leak