Before going into the battery problem, please tow the jeep with another vehicle with the jeep in gear to see if the jeep motor itself is frozen. 1945 was a long time ago. Of course, make sure the motor has oil, fuel and good spark plugs and distributor (points) before towing. If you can get the motor to run, then check the other answers here in Yedda to find a possible battery. All this is assuming that the 6volt battery you've tried is NOT the square one that you put in a large flashlight. That type just WON'T work.
