Hi Gabby,
There are lots of us that started out on M series trucks and worked backward into Korean and then WWII era trucks. The WWII Chevy's and GMC's are some really classy trucks. I have owned G506's and currently have a 1945 GMC dump truck. A couple of thoughts come to mind. There are a number of people that are experts on the WWII trucks in your area (NH) that can and will help you. The Chevy G506 is a nice size truck. All the looks of the big 6X6 but smaller and with four fewer tires. Bigger than a Jeep so you have to drive it to shows, rather than trailer it, but you have room in back to take your camping gear for the weekend. The enclosed cab is small, so don't try and put more than two people in the cab. They are a little hard on gasoline, but what 1940's truck engine isn't?
The original engines were lubed by a low pressure dipper system and many G506 engines have been replaced with later models that are pressure lubed. They look similar. Get someone to show you the difference in the truck you are looking at. Brakes will require a complete rebuild. When the brake system dies, the whole thing dies. Parts availavility can be spotty. Sometimes the NAPA store can help since many components were commercial items used well ito the 1960's. Other chassis parts are getting harder to find. Some folks give up on the 6 volt electric system and make a convertion to 12 volt. That can be done and there are opinions and articles pro and con.
Does it have an original cargo bed on the rear? These were usually discarded and are probably the hardest big part to find to restore one. You can also look at the web site
WWW.CCKW.org. Lots of Chey G506 info and contacts there too.
Remember these works of experiance...."Always buy the best most complete truck you can. They cost more, but that cheap clapped out wreck will cost more to restore in the end."
Welcome Aboard.
Cat Man