GM# 3831194 comes up in my search as the correct part number for the 292 lower alternator mounting bracket. Fits 1963-72 C-10 thru C-30's w/292 engines (not for AIR, 62 amp alternator or HD water pump equipped trucks). First pic below is a pic from a 1970 Chevy Truck Master Parts Book showing the design for C10 thru 60 6 cylinders reference.
Your number "3831195" didn't come up in my searches. Possibly a typo?
Could be someone swapped out the balancer and water pump and you may need to get a different lower mount bracket. The same period 230/250 lower alternator brackets (GM# 465826) puts the alternator over an inch farther forward, but has a rear bushing that can be moved to the rear (gap created forward would need a spacer or washers to fill) to allow for alignment of the alternator with your current pulleys in the new bracket.
A new 230/250 style bracket can be found from lots of various aftermarket sellers. A sample is pictured also below.
Before jumping in, please post a picture of what you currently have as that needs to be confirmed before chasing this rabbit.
