BAD INTENT

I joined this site to try and find out about the vacuum system.What is the minimum vacuum lines you can get away with? its a spaghetti nightmare on my 83 720.My truck is a base truck no ac nothing but has had an 89 engine installed before I got it.The previous owner installed new exaust and sounds like and old john deer pop pop tractor another issue plus it has no power I need to start my own thread for these issues but again least amount of vacuum lines??