360 stroker with vibration

What torque converter you running. If you went for the internal balance on your 360. Then you will need a neutral balanced converter, flex plate, and dampener.

You didn’t buy a balanced rotating assembly to begin with piston, crank, rods etc. therefore you needed to have those parts balanced before assembly.

I hate to say it but the best case scenario is probably blow it apart again and have a machine shop balance it, better yet maybe have them short block it for you.