On the distributor cap there is an extension that juts out toward the driver side. underneath this are two wire terminals. they should be marked on the top of the cap "Tach" and "Batt." A wire with a male spade end crimped onto it fits into the "tach" terminal and provides a signal for your tachometer to use.
Connect the green wire to the negative side of the coil.
on the drivers side of the distibutor cap using a blade electrical hook up you can plug into the opening or if there is a wire already there splice into it make sure all your grounds are in place or you will burn up you coil
If it is the HEI there is a terminal toward the bottom marked tach this is where the trigger wire will go (usually green). Red to switched power,black to good ground, yellow is switched light( anything that comes on when the light switch is activated.
It can be done, yes. You could even hook up a digital display which shows your RPMs, fuel efficiency, engine fault codes, etc. if you wanted. They're available.
if it is a hei ignition there is a place on the distributor cap that says tach.
For a 1987 Chevy pickup with a 350 engine and a non-HEI ignition system, the wire that is typically used for connecting a tachometer is the green wire located on the distributor cap. This wire provides the signal needed for the tachometer to work accurately. Make sure to consult the vehicle's manual or a wiring diagram to locate the specific wire on your truck.
If the 350 engine is a carbureted engine and not FUEL INJECTED, Then remove the 327 and install the 350 and hook everything back up and your done. They are the same blocks other then the stroke.
no
Could be the tach is set for 6 cylinders?
First of all Chevy did not make a vortec engine in 1987 or 1995, those engines are TBI / Throttle body injection engines. And yes they will interchange with no problems.
NO.
YES.