On the '94, you probably have a 'Z' engine and you'll need a distributor with top-mounted plug wires. If I am wrong and you have a 'W' motor, you'll need a distributor with side mounted wires (serious pain).
They are both top mount plug wires. It was not until later they had the side mount wires. Vin "Z" is a TBI (throttle body) Vin "W" is Vortec. TBI has breather mounted on intake Vortec says Vortec on Intake
4L60E.
R134a
5w30
4L60-E
Obd ii
rocket fuel
15 to 18mpg
If the Blazer is gasoline powered the antifreeze can be any kind that is for sale for gasoline powered vehicles.
It will be a 305 or a 350 fuel enjection engine ( TBI )
700 R4 if it is automatic. 2x2
You should have this verified but the freon is probably HFC134.
That would be a 4L60-E transmission.