Check some basic stuff:
Does the check engine lamp come on when you turn the key to the on position? If
not, you need to investigate why the engine computer doesn't power up.
Check your fuses. One or more may be blown. This could be due to a pinched
wire during disassembly or reassembly (i.e. may need to fix a wiring issue in
addition to replacing fuse).
Are all the ground straps connected? If not, this could prevent proper
operation of a number of components.
Are all the wiring connectors put back on the proper components? Be sure to
check carefully any connectors which could be easily switched with another
Do you have 12V power to the coils and crank sensor when the key is in the on
position? If not, you'll need to troubleshoot those circuits.