In a 5x8 Uhaul trailer you can fit 6 pins... 3 modern pins and 3 pins with heads detached and in the pulling vehicle. You can fit 3 modern pins and 2 with heads detached and in the uhaul trailer. A 5x8 sits far enough back that you can open and close the trunk of a SUV while the vehicle is attached. I do not know if you could fit 4 modern pins at once.
In my particular case I brought:
Fathom Head detached and in lead vehicle. Strapped sideways and across from Gottilieb Super Mario. Next row was Flash Gordon and Spiderman in the same way. Final row was Stern Jurassic Park, a one up, and a dolly at the very end. Pics to follow.
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