[old Chevy guy]

Update, so far I checked the fuel presure,its good 63 pounds.I checked for spark,has spark but is decidedly weak orange yellow.Tried diffrent coil and ignition modual that I took off a running motor at the local garage.Still no run also no improvment to spark.Next I will atemp a diffrent distributer which will include another cam senser,and if that dosent get it I will change the crank sensor next. Anybody know what could cause a weak spark? More updates latter on.