In your case you may want to try for an exchange unit from harbour freight. I agree they are not that great to put it mildly..You did eventually get indications your engine is not really low compression though and that should be a relief. Your cylinders are still within 10 percent or very close as well and that is allowable. Was the injector adaptor leaking because of a poor heat shield? Or did you see some other cause you might have identified?

The leak was coming from the attachments to the gauge. I had leakage problems with both the injector attachment and one of the glow plug attachments.

Scott