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so if i am getting this right the feeling is it is a field wire? or the alt ?


Could be one or other or both.
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i have a spare alt and i did a contiuity test on the field wires and they were good but one could be grounding right?


Yes. When you check continuity on field wire terminals, you want low or no resistance, IIRC (I could be wrong there). BUT, you also want to make sure that there is NO continuity between either one of the field terminals and the case of the alternator (indicating a brush short to the case), that WOULD cause the alternator to charge like mad. And if one brush were shorted to the case, that MIGHT cause the symptoms you described.

I'm no electrical guru, but if I were doing it, I'd try to either get the alternator tested - which might not prove anything other than it can put out it's rated power, which we already know, OR swap in a known good alternator, which would eliminate one source of trouble.