I've got a 1978 and I'm running through the same problem!!!
Car was running fine until I parked!
6 weeks later, battery died. Put a new one, and now it will crank but no start. I have great spark, but no fuel, no fuel pump noise, nor power to the injectors!!!
I hooked power to the fuel pump and had gas being pumped out from the fuel line before the injectors, so, fuel line is not cloged, and fuel pump works!
My car has an aftermarket alarm, but it sounds weird though, I never had any problems with it!!!
So My guess it's something related to wiring or to fuse or relay somehow!!!
I'll look for that red wire tomorrow!
Let me know your progress and good luck!
Gunther