3.1 timing issues

Ever since I changed my intake mani gaskets, I cannot get my truck to start. I have:
1. Set the valve lash
2. Set #1 to TDC
3. Dropped in the distributor with the rotor pointing to #1 on the cap
4. Disconnected the plug next to the ecu (one side is white and one a kind of green)

If anyone can help I would greatly appreciate it

Thanks
Randy