timing light to alternator

[funnycar]

had a perfect 63 polara running car before i turned my back and seen the timing light my buddy hooked up to alternator didn't give me time to tell it was in trunk next thing i know whole wire harness is just up in smoked couldn't believe no fire. Scrambled get trunk open and pull cables .no damage beyond wire harness engine bulk head side.he said had positive on hot wire black on ground .
was told you dont do that can some one verify. Have ad for engine harness on wtb form .
thank you

 

[65wgn440]

No problem hooking up power to timing light at alternator output post. I've done it many times. Your alligator clip probably swiveled a bit when you were setting timing, and shorted out against alternator housing.