need help/ not charging..I think

so...let me get this straight....

I have 12volts up thru the bulkhead with key in run position..motor not running...thats good

when motor is running I still have only 12 volts...checked at positive battery lug near engine compartment....thats bad...means not charging

all dash lights /switches/guages/ now working as designed...thats good

it just dawned on me that the local automotive electric repair shop that changed out the stock plated pully for my matching powdercoated pulley said they had to disassemble the alternator to install the pulley....I'm just spitballing ...but I'll bet they forked something up.....

It will be at their repair shop tomorrow for sure