The plan is to cut the angle (former bed frame) you see in front down to 3 ft. That way there is another 3 left for the opposite side. Use three bolts through the frame and the angle insert
The two rails are 3 ft each for a total frame length of 6 ft. The spring hanger is placed where it is for wheel placement. As you can see this puts the joint in the frame directly above the front spring bolt. The post-it notes indicate where I will cut the angle and where three bolts will go through the frame and angle to hold it all together.
I believe that it should do the trick when I consider the Andrew ‘ultralight’ frame is a non-frame. I don’t want to/can’t use the regular frame rails inside because they are too jacked up- bent, tweeked, non-true.
So, does this seem like a plausible plan?