Headers for LS3/1952 Chev PU

[Gabbyp]

This is an update to my initial post. I purchased Speed Engineering and have installed them on my 52 Chevy truck. This is a mockup as I have not welded any mounts to the frame. My concern was is the narrow frame rails would not allow clearance. They fit with clearance on both sides. I have an early 4l60e trans from a 1990's truck again for mockup and the O2 connectors rub against the trans flanges on both sides. I don't know if the correct 4l60e for an LS engine would have this rubbing concern. Some members have ground down the flanges to give clearances. So far I think this is going to work. Pictures show the rubbing concern. Any comments or thoughts would be appreciated.