1996 Chevy S-10 won't start cold

I would first check the fuel pressure. It could be leaking residual fuel pressure. The way to test this is to connect a gauge to the test port(probably schrader valve on fuel rail) and turn ignition on(engine off) and this will operate the fuel pump a few seconds. Observe the max pressure on the gauge. Depending on the type of fuel system it has it should be:
MFI-41-47psi (4cyl)
TBI-9-13psi
CMFI-58-64psi
CSEFI-55-61psi
the pressure should then hold steady after it reaches max pressure. (Residual pressure). If it does not hold your fuel pump check valve (at end of return line), fuel pressure regulator, fuel lines or fuel injector may be leaking. This could cause a hard start or no start.
At regular parts stores these gauges are around $40. But to me they are priceless in diagnosing.

In a 4 cylinder you have to hook up the gauge at the fuel filter connection. Take the filter off and hook up a gauge there.

(not sure which year they made what)

in a 4.3 v6 throttle body(carb looking unit on top)
you have to hook up the gauge between the fuel in line and the throttle body itself.

In other v6's CMFI and CSEFI you hook up to the schrader valve on the fuel rail.