Can a older block be used to replace a vortec block . I have used a older throttle body block ( 94 ) to replace a newer multiport injection block. I switched heads and intake and seems to run but, not right. I am getting a cam crank correlation signal code and have went completely through all sensors and systems and everything seems to be fuctioning properly. Is dumping to much fuel at idle .

if by interchange you mean bolt in sure it's the same block they didnt change any of that till 2004 , but if you mean plug in to all the injection and sensors nope sorry every model year they change the plugs around and it's got a difff kind of MAF sensor on it

The regulator is usually mounted on the fuel rail in multiport EFI (Electronic Fuel Injector) applications, or the throttle body assembly in throttle body injection (TBI) applications.

• Some fuel injector types require pressure regulator replacement as an assembly. There are repair kits available for other types

Look.
If you see a fuel rail or a short-throat throttle body, it is fuel injected.
If you see a carburetor... well, I think you get the point :)
From the year (unless it is a non-U.S. model), it is most likely FUEL INJECTED.

Lets start with terminology. I am assuming the truck is newer than 1987 so you would have fuel injection. No carb.
If it is a vortec engine, either a 4.3 or larger, and built after 1993, it could have central port fuel injection. That style uses one injector and a spider of lines that go to each intake port. This is inside the upper intake manifold.
Vortec engines require more fuel pressure than engines with port fuel injection or throttle body injection. So the first thing you need to do is check base fuel pressure before and after you crank the engine. You'll need a pressure gauge to do it. Normal fuel pressure at idle for a port injected engine is 35psi and 60psi for a central pfi system.

pass side below front of cylinder haed on block, there wiil be a number with letters. give those numbers to dealer.

The 1995 350 is a "Vortec 5.7" motor if I remember correctly.You will have to get a throttle body and intake manifold for an older 5.7 liter(early 90's?).The Vortec engines are a sequential multiport injection setup(totally different).

If its a throttle body injection or multiport fuel injection the fuel pump is in the gastank, If it has the optional carburator for that year then it is on the engine block.

if you have the 4.3 then you will need to take off your upper manifold/throttle body which is the big piece that your vortec plate is on, then you will find it with your spider assembly fuel injection it is the part that the electric and injectors go to. have fun

There are two kinds of injection... throttle body looks like a carburator, and has one or two injectors in it,
Multiport has an injector for each cylinder. A multiport wont have a throttlebody, but both do have other parts, like an idle air control valve, and other items that could be cleaned.
I would recommend adding injector cleaner to the fuel, and spray some carburator cleaner into the intake while running. Just an idea!

any body parts from 1988-1998 will interchange.(except box parts stepside vs fleetside Grilles and head light/front signal lights differ from year to year but an newer grille can be put on an older truck as long as both trucks have the same headlights) As for the complete engine you can use any throttle body engine from another truck But you are best to keep the computer or at least the chip with the corresponding engine. the computer can be found behind the glove box. I believe the ones that will work with your 94 are 1988-1995
Hope this helps!