Once you get the cat replaced do a search on these pages for "setting duty cycle". You will be able to dial in pretty darn close without an exhaust gas analyzer. You will need a digital volt meter capable of reading duty cycle. If you don't already have one, Sears sells a decent one for about $30 or so.

__________________
Mike Tangas
'73 280SEL 4.5 (9/72)- RIP
Only 8,173 units built from 5/71 thru 11/72

'02 CLK320 Cabriolet - wifey's mid-life crisis

2012 VW Jetta Sportwagon TDI...at least its a diesel

Non illegitemae carborundum.