well after breaking the coupler , accidentally, at the line i have determined that the reg is just pulled off of the connection but you have to pull quite hard to break it loose. the new one would then just be pushed back on. i figured since i already broken the coupler just play with it and that is how i figured it out. but since i broke the coupler at the hose i will now be using a reg with a barbed end and hose clamp.