[aprssig] Tractor symbol?

[David and Ann Fraser]

A local ham has a tracker on his tractor but has been unable to find a
suitable symbol for it.

(By "tractor" I mean the four wheeled machine that is used to drag
ploughs and similar agricultural implements around fields, big wheels
at the back, smaller ones at the front.)

I haven't found a suitable symbol in the symbols.txt file of APRSdos or
the APRS spec, and wondered if some symbol for "agricultural vehicles"
such as tractors and similar vehicles should be developed?

David ZL3AI.