I recently changed my alternator and replaced my idlers and belts.
The AC belt on the N62 is a PITA.
Turns out the AC belt adjustment is T40 Torx that you reach from the bottom. The T40 is NOT fun trying to get to with a 3/8" drive T40, I was able to get is, but I had to go back and tighten the belt more.
I purchased this 1/4" drive kit on ebay for $23 that had a T40 1/4" drive rather than a 1/4" drive Torx bit set at T40 in 1/4" is a bit tricky to find.
46pc 1 4" Drive Socket and Bit Set Metric Hex Pozi Star Phillips Slotted | eBay
I then used a very long (12"??) 1/4" wobble extension I had already and the T40 Torx bit to get to the adjustment. MUCH easier than with a 3/8" T40 Torx bit. I could have used this set by its self, but found the long 1/4" drive wobble extension gave me another angle from further back than the shorter extensions did not give me.
Some red Loctite and the proper size nut installed on the other end of the adjustment bolt might be another option so you could get to the adjustment from above might be what some would choose to do. Not sure how long the Loctite would take to cure or what thread size the adjustment bolt is.