2.6 belt tensioning (voltage regulator)

So I lost all power on my 2.6 @155k after a crazy storm in California. I've been in ownership for a year and have roughly $3500 in maintenance records invested in my smoke silver w201. I've always had fuel issues with the car and am due for new fuel injectors. That is not my problem today. I had just replaced my blower motor with a nice quality unit from MB the night before (which still needed to be filed down for an extra quiet blow). DIY'r here because this car is getting very expensive. Luckily, I was able to limp the car to a safe area without completely dying...which by the way was the most gentle way I have had a car die on me. lol..so it is NOT a dead battery. ABS and Airbag light were on. Started the car an hour later and limped it across the street to Autozone where had a replacement alternator to wrench and get me back on the road.

A YouTube video mentioned loosening an 8mm Allen socket pulley along with the adjustment nut and the mentioned 19mm belt tensioner nut. Upon this procedure, the entire unit shifted leaving my ratchet paint on the radiator after moving the 8mm Allen socket. It did buy belt slack obviously, but it did leave insane dent damage on my radiator. Can the balancing of the belt/pulley system be "thrown off" by loosening the pulley holding an 8mm allen socket?

I did not use their unit, the OEM pulley did not reside on the replacement..But my alternator was out of the car and called a tow. After a night of peril, it ended up being a voltage regulator after careful inspection of worn brushes and soul searching the forum. I will start there with getting my 2.6 back on the road. Big fan of this chassis, it is due for some serious DIY maintenance overhauling.