Found my #77 fuse blown?

Checked the number 77 fuse in my Chevy Colorado it was blown replaced it and it instantly blew again my ac only blows heat so I started with the fuse box and this happened

Fuse 77 goes through the AC compressor relay and from there to the AC compressor. Try this, key off, install a test light in place of the fuse. That will keep you from blowing fuses during testing. With the key on but AC OFF, watch the light. It should be off as the relay should be off when the AC is off. If it's on there is a short, Remove the AC relay. Light goes out, the short is after the relay. Possibly the AC diode or the compressor itself. Unplug the compressor, light goes out? We need to check the compressor clutch coil for damage. That is a bit harder as the coil is nothing but a long piece of wire, the normal resistance is from 2-5 ohms. The problem is there is no hard numbers but generally below 2 ohms is shorted and bad. The GM units I've tested run about 4 ohms.