Hello, Just bought a 2005 crossfire SRT-6 I live in Iowa and it gets pretty cold here just bought a cartridge heater from Napa in trying to figure out how to put it in. There he is supposed to be a special opening on the block so you don't have to pop a freeze plug. I guess I will let you know how it goes. The part number is 605-1649. I will keep you updated on my progress