Early Ford V8 COE help

[EJOWest]

I’m wondering when the Gauge cluster changed from round gauges to rectangular gauge cluster?
I’m looking at a COE and the seller thinks it’s a 1940 but it has Rectangular gauge cluster opening in the dash (gauges are missing)
The grill is missing as well but I believe 38-40 were the oval grill and 41-47 was the bar grill type correct?
Thanks!

 

[Cool Kat with Hot Car]

My 40 COE has the pair of round gauges. 38-40 have the barrel nose.

 

[EJOWest]

Thanks, The cab is in pretty rough shape but there are some clues.

 

[flatrod]

My 42 has rectangular gages. I am told 41/42 have no window frames, whereas 47 has framing around the door windows. I do have the bar type grill.