Fuseable link?

[80chevyshortbox]

so i pretty much F**ked up hahah long story short i was conecting my battery and i connected the -to+ and the +to- when this happend a little peace on my firewall burnt up. is this my fuseable link and if i just replace the burnt wire will my truck still be ok? has any one been as dumb as me to do this im so mad at myself. im just praying it wont cost me but i have a really bad feeling it will.

btw i never put the key in the ignition or anything right once i connect the terminals it burnt up and i took them right off.