Thank you for your advice.  I now have the courage to give it a go!

Scott

If you have a sealed beam then there has been and adapter kit added to your car. You would pull the unit out exactly the same way as elmo described it.... Unscrew the bottom screw, push in at the bottom and pull out at the top.

chrysler used the same system for 36-37-38. this is the instructions given in my manual, loosen the screw at the base of the headlght body , using the lens removal tool ( its a suction cup tool ,i used a panel beaters suction cup that they used for pulling shallow dents in body panels) push inward at the bottom of the lens causing it to come out at the top of the body, and withdraw it upward and out from the body . after braking  a lens i soon learnt to place some thing soft on the ground , just in case , for that i found a babys cot matteress ideal . but if your truck has a sealed beam unit it would be more than likely it has been replaced some time in the past, and the procees i have just given wood be different .

I have a 1936 Dodge PU truck that I believe is identical to the Ply. except for the badging.  ("Same difference" as they say in Indiana.)  There is a retaining screw on the bottom of the headlight ring & once removed it is looser but appears to be held by springs.  I hesitate to force it, so would appreciate some guidance.  The bulb appears to be a sealed beam.  My service manual is silent on the issue. Thank you, Scott