That would be the 400 turbo.
Yes - probably a long time ago
YES. The 74 and 86 engine blocks are the same as far as DESIGN.
There are 6 bolts that holds the transmission to the engine.
The 86 2.8L automatic transmission will not bolt up to a 71 Chevy engine.
Depends on mileage, condition, engine, transmission, and options. Click the link.
yes
On a 1986 Chevy 4.3L engine, the vacuum modulator is typically located on the transmission, specifically on the driver's side of the transmission case. It is connected to the engine's intake manifold via a vacuum hose. To access it, you may need to remove some components or hoses in the vicinity for better visibility. Always ensure the engine is off and cool before attempting any repairs.
junk yard
There is only one.
YES.
The car has a 700R4 transmission. 4 speed automatic
The transmission oil goes in thru the dipstick tube.