straight axle 63
I have some pictures of how to remove those steel plugs and weld in some aluminum slugs at
http://community.webshots.com/user/OldFartEdThe cost of welding should not cost very much. Just make sure that they pre-heat the area to be welded and then let it air-cool after welding.
If you do go with this 'water heat' route email me at rncrecording@hotmail.com with your name and address and I will send you a couple of aluminum slugs that will fit right in.
Although I'm a believer that 'hot-air' heat is better than the 'hot-water' heat if you live in a area that gets cold in the winter time. Like I live in Illinois and recomend the 'hot air'.
With 'hot-air' heat you just use your intake the way it is, you would not need to do any welding. They were actually designed for 'hot-air' use and not for 'hot-water' heat in the first place.