Alternator belt

[Charger440]

I have a 1977 dodge m400 motorhome with a 440 and automatic 727. This motor and transmission has been a dream to own since I was a child. My plans are to install the motor and transmission into the ultimate build of a 1969 Charger R/T and convert the auto 727 into a standard.
I am currently have issues with the alternator belt. Last night I replaced the plugs, cables, cap and rotor. Sparks are gapped at .035. A couple weeks ago I replaced the "behemoth" of alternators. I am new to mechanics and have been self taught.
When starting up, the Belts scream and there is a ticking noise coming from the alternator as if it were hitting something. Belt shakes bad at idle but straightens out during Rev. I have checked and checked again, the alternator is not hitting anything. Neither is the bracket. I was advised to tighten the belt. When doing so at idle it looked much better. During high Rev suddenly I smell something burning. I look down at the Belts, and the alternator belt had twisted and nearly came off the crank pulley. Got rather chewed up. What did I do wrong? Was the belt in the wrong groove on the alternator? Too tight?

 

[Plymouth 65]

Pictures are worth a thousand words! You may have simply installed it incorrectly. The noise from the alternator could be bearings if it's not hitting anything. 65'

 

[Dana67Dart]

With the belt off, spin the alternator pulley. It should spin freely and have very little noise. the feel should be smooth as well (NOTE: there are brushes in the alternator and when spinning can have some feel and noise to them)

 

[Charger440]

this is the best picture I have so far. I was running late for work this morning when this happened. So i loosened the alternator, took off the belt and headed out to work. I will take more pictures this evening. I will give the pulley a nice spin and go from there. I am thinking it was on the wrong groove.

 

[ACME SS]

So with a squeal, if you pour water on it and the noise goes away, it is the belt (probably loose). If the noise does not go away, suspect a bearing. The fact it rolled means one of two things. 1. you have the belt in the wrong pulley (i.e. it is not straight). Belt alignment specs is something like 1/16"-1/8" per foot or something like that (used to teach this subject but its been a couple years). or 2. If you used a screw driver or equivalent to pry the belt onto the pulley, a belt can be damaged and if so it will roll like that. Oh, and although they sell belt dressing, none of the belt manufactures will recommend you use it.