Would like to perform a compression test on my 85' OM617.

Where can I pick one up? Any links would be great? Is this something I can pick up at Autozone or Sears? I remember a while back seeing a diesel kit that had adaptors to fit several injectors etc. If so what are the thread size for our Bosch injector bodies?

Also what are the PSI recommendations for a healthy motor. More importantly what are the practical variances btw each cylinder. 10-20%

Im assuming that the test must also be performed with all 5 injectors off and the car on Neutral.

Thanks