I have a 1977 Cutlass Supreme Brougham 5.7 liter. All stock. I have only had the vehicle maybe two and a half months. After removal of the AC compressor there was a lot of belt noise coming from the alternator. I assumed it was because possible pressure on the crank only coming from only the driver side. So i aligned the remaining 2 belts (power steering, alternator) and secured them tightly. And in doing so i beleive my front and back intake bolts stretched and possibly cracked where the EGR mounts to the head. Has anybody ever seen or heard of it before, is it necessary to mount the alternator to the other side of the engine as if it were to come without air conditioning from the factory.

 

The only particular concern with running accessories on only one side is sometimes that will wear out the water pump bearings, leading to a water leak. Even then, it takes time. Getting an old belt system to run quiet can take some work. Make sure all the mounts are solid, nothing can wobble, all the brackets are present, and new belts usually help.
Moving the alternator to the passenger side will probably require a complete set of brackets and pulleys from the donor configuration. Just depends on whether the offset in those later years matched any of the earlier stuff. Passenger side alternator brackets aren't terribly rare - post a parts wanted ad here and you can probably get a set to experiment.

EGR? Do you mean an AIR pump?

 

Take pics of the suspected crack and your belt set up. The G body Vin Y belt set up needs the A/C compressor in place. I assume your 77 has the 3 groove crank pulley like my 76 had. If it also has the dual groove power steering like my 76, even better. Did you remove the A/C to clean up the engine bay?

 

No, it won't. Do the math. The net side load on the water pump shaft is DOWN, towards the crank, no matter how many belts you have. This is yet another myth that refuses to die. GM sold a LOT of cars with only one belt (no PS, no A/C). Why don't those fail the water pump?