Has anyone had the issue with the behind the cat O2 sensor leaking exhaust fumes and completely giving out? Mine has done this now and I am trying to figure out how to prevent it a second time on my 98.

That isn't normal. The sensor has a crushable washer like our spark plugs. It will seal when properly torqued. Over/under torque would cause it not to seal. You may also have damaged threads or the bung welds are cracked.

Dang thanks for letting me know I will check that out in a few minutes I just picked up the new 02 sensor now