Need some help

[Hatch guy]

so my 72 blazer was running alittle rough the other day so i decided to change the carb, plugs, plug wires, dist. cap, and rotor. i did all this now it wont start. Checked spark at the wires, nothing. Check spark coming from the coil, nothing. Any suggestions on why it started this after i changed all this. Is there a ground i knocked off without realizing or can a coil just go from starting to bad like this.