I am not sure what is correct size is for a serpentine belt for alt, ps and water pump on 1 95 m50. Found discussion in archives about AC belts but not anything on the M50 PS belt.

REALOEM states 6PK x 1555
Autohausaz and others state 6pk1560

Looks like the Autohauz belt is a bit longer? if correct, this may explain a squeal I have on cold start if I have a belt too long and has stretched. Any thoughts? TIA