sorry about the pic link...can't seem to figure out how to post a pic. this is the direct link: http://img.photobucket.com/albums/v85/barndwellers_md/002-2.jpg
I found out I had to hook the supply line up right above the temp sensor (there's a plug to remove) behind the thermostat in order to make the loop active. For some reason the B series is different. Not a lot of room, but made pipe fittings work.
can I ask which heater you used and how it fit?