I'll have to snap some pics, but what I did was tack weld a piece of flat bar to the bottom of the frame in the spot I wanted all 4 tubes to merge into the collectors. That gave me a target instead of just imagining where the would come together. I tacked 4 scrap pieces of tube together for a visual aid. So far the passenger side has been easier - the side with the tubes "stacked" in the pictures above. I need to get some more bends as it seems I need quite a few that are less than 30 degree bends and there were not too many of those in the assortment