360 stalls on deceleration from throttle blip

Yep it’s a project! I new a lot needed to be done when I got it. I’m just starting out. That’s why I posted was to get some pointers where to start. Thanks for those things you mentioned. So question about the vacuum advance line. I haven’t touched it since I got it but I was doing some research and noticed what you were suggesting to move it to the ported but I heard conflicting accounts online. The Eddlebrock manual says the side it is currently on is for non emotions engine. All that stuff has been removed as it’s a 73. But I was unsure as logically I would think it should go to the passenger side in order for vacuum advance to do its job because currently the drivers side hook up would be a vacuum even at idle correct? I’m open to recommendations! I just couldn’t get a clear read online so I appreciate your help. So do you think the current funky linkage could be causing my issue? Perhaps it’s springs back to quickly. Or it could be the vacuum advance issue. I’m just trying to figure out what order to proceed with things
Yes...pass side port will be ported vacuum...none at idle. If you're setting your timing with the vac hose connected to the manifold vacuum port, you're getting vacuum advance at idle, which is messing up your readings.