348 Alternator Swap

Hello gents wondering if anyone could tell me if a 355 alternator is a straight swap into a 1990 348 ts, my car has the updated kit for the nippondenso alternator, but the previous owner replaced the alternator with an alternator that does not have the correct 3 pin plug only a 2 pin plug, therefore my alt dash light does not work. I would like to change alt, I have a line on a 355 altnerator, but I want to be sure it will bolt right in with out changing mounting brackets on the 348. Thanks for all the help.