Decided to just go ahead and build the first proto with round tube. I will need to smash the ends to mate up with what I was thinking design wise, but that's really not the end of the world, and likely far cheaper. I was so caught up with the look of it, I forgot that what I'm really after for now is functionality. So...that would mean the first one is steel and round. If I get it worked out, I'll want to go aluminum and honestly, I'm not sure the square is necessary at all.
1978 13BT-40, 70 series mechanicals
1966 FJ45 lwb stock
2003 100 stock
1974V8J40, 1992FJ80, 1985FJ60, 1971FJ55, 1978FJ40, 1974FJ40, 1997 LX450 all long gone.