I have a 10 yr old Bradford-White 40 gal LPG water heater (#M-I-40S5CX- that last month all of a sudden started dripping water out of the overflow tube (about 1 gal/day, but getting worse as time passes). From what I’ve read on other posts, it appears to be a temperature & pressure revief valve that has gone bad. Replacement doesn’t appear to be a complicated job and I’m pretty handy. My question is: what is the proper procedure? (My guess: turn off gas supply to heater; turn off water supply to heater; let water cool; drain some water from valve to release pressure; disassemble drain; unscrew valve; screw in new valve (w/ teflon tape) and reassemble drain; turn on water and gas.) How close did I come?