Good evening. I bought a sight glass level indicator for my Gledhill Pulsacoil to replace the old one as it was leaking and my tenant broke it in an attempt to tighten it up. Do I have to tighten it up by hand or shall I give it a 1/8 of a turn with the spanner? Does the O ring go on the outside or the inside of the tank? Thank you for your time.

