1974 Dart 2nd fuse blowout
Number 2 fuse on '74 A-body feeds:
Heater blower switch
Radio
Reverse Lamp switch
Turn signal flasher
If you have a multimeter or test light, leave the fuse out and check for continuity to ground.
I think the best initial approach is as suggested above - retrace what you did looking for wire cable that got caught or crunched.
If that doesn't work, then with with fuse out, start disconnecting the connectors and checking for continuity to ground.
Circuit is almost the same as a '73 which we helped someone with not long ago. His ground short was a wire on the transmission but that's neither here nor there. You were working on heater blower so that switch and its wiring is a likely area.
Number 2 fuse on '74 A-body feeds:
Heater blower switch
Radio
Reverse Lamp switch
Turn signal flasher
If you have a multimeter or test light, leave the fuse out and check for continuity to ground.
I think the best initial approach is as suggested above - retrace what you did looking for wire cable that got caught or crunched.
If that doesn't work, then with with fuse out, start disconnecting the connectors and checking for continuity to ground.
Circuit is almost the same as a '73 which we helped someone with not long ago. His ground short was a wire on the transmission but that's neither here nor there. You were working on heater blower so that switch and its wiring is a likely area.