Great progress
I have learned a Few tricks over the years about bed bolts.
Especially the Later model Square body has 2 bolts that are (Long).
1st thing I do is Drill a small 1/4" to 5/16 hole in the center of the Top of the bolt that is spinning / about 1/2 to 1 inch deep.
If you have someone to hold the bolt from the bottom while drilling (If Needed) it helps.
Then take an angle grinder and very carefully cut and X in the top of the bolt.
Tack weld the bolt lightly to the bed.
Then try your luck breaking the nut loose.
Only put penetrating oil on the nut not the bolt.
Ask me how I figured that out.
If this does not work or the bolt breaks the welds.
You have several options.
Reweld the bolt then drill the top of the bolt with a drill bigger than the Diameter of the bolt, (1/2 ") maybe use a 9/16 or 5/8 drill.
This will separate the head from the shank of the bolt.
An undesirable option would be to drill the bottom of the bolt or grind it off.
I prefer to do the grunt work on the top (Less sparks, shaving and dirt in your eyes and stuff)
Hope this helps.
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