exhaust gas temp

I Have a leak around the fitting in my exhaust for my EGT and I wanted to know if anyone knew if there was anything on the threads to help it seal or how you guys sealed yours into your exhaust. I was also thinking of maybe using silver solder to seal the fitting. It's making the o2 read lean at...

I am Installing a pyrometer(EGT) with my SDS. I am Installing a GTS upper intake manifold and the Ripp New design headers. to my understanding Ripp slightly legthened the #4 pipe to help counter the lean condition with the standard GT intake manifold. My question is what is the best Cyl to tap...