Alternator trouble, Nissian N16

[aye you]

Hey all,

recently changed the alternator on the missus car. was working great. Today the battery light came on, got home, chucked the multimeter on it, battery showing 12.8v. So i had a look at the positive post on the alternator and noticed it was sparking and the contact between the lead and the post was poor.

I obviously need to make the contact better because when i fiddled with it the light went out. Ideas on it, i still have the old alternator if i'm able to somehow swap posts over.

Is that possible, or do I need to just change the bolt?

Also, im a stupid move on my half, I thought I'd be able to finger tighten the bolt, wearing gloves, but the bolt burnt right through the glove and into my finger, which I can barely move at the moment.