Belt diagram for a 1978 w/305 and A/C
 

I recently installed all new belts thought I did it right but maybe i didnt. Everything seemed to work but I noticed the the alternator doesnt seem to work properly. I charge battery and after about 5-10 min of running voltage drops and only stays running if i keep giving gas. I think maybe i didnt install belts properly. I Have a stock setupo 305 with a/c and no air pump. Can someone please help and provide a decent picture of the belt layout I can follow? None I find look correct for me.

Thank you in advance.

I would get an assembly manual for your car .Amazon and others have them for around $20-$40 .

You said four belts but I see only three in your video. The fourth belt would be for an air pump that wasn't used in 1978. If I remember right the inner one goes around the crank and power steering. The middle one goes around the crank, water pump, power steering and the AC compressor. The outside one goes around the crank, water pump and alternator. Put all the belts on then tighten the power steering pump first then the AC compressor and lastly the alternator. Good luck