wont start

i have a 91 1/2 ton chevy with the 5.7 engine. i had to replace the intake manifold gasket. today i put it all back together and now it wont start. it will turn over but wont fire. i have no idea what to do next. please help.

Did you set the dist right ?

Rotor pointing to TDC compression on no one cylinder and is rotor turning?
Does it have good hot blue spark to all plugs?
Got good fuel presure?
Got power and injector pulse at injectors?