And as far as letting it freeze. The freeze plugs did their job as it seams. I only left water in one side of the block and I'd guess the cylinder head didn't have water that high up just had water in the passenger side block
"Freeze plugs" are not for freezing. They have NOTHING to do with freezing or freeze protection. The name is an old wives tale just like removing a battery cable on a running engine to test the charging system.
"Freeze" plugs had one purpose and one purpose only.......to allow the factory to cast the block.!!!! The proper name is "core plugs."
Your light won't flash? Is it inductive? Try flipping the pickup around and moving it on the wire. Otherwise, it might just be a bad light.