LX Kid,
We are still waiting on the machine serial number and any other info you want to include.
Judging from the nameplate you showed, the serial number should be stamped into the top of the front way near the right end. It may have letter(s) prefix and/or suffix to the digits.
Although I am working on one, it won;t be ready any time soon. But Atlas or Sears never did an exploded view parts manual on the 101.07301. So from Downloads get the 101.07301 parts list that we do have plus download the 1950 version of the Atlas 618 manual. Much of it is the same except for part of the headstock. and part of the countershaft and the bed and legs. In particular, the Lead Screw and Feed Gear assembly is the same. As it originally shipped, the 101.07301 had five gears and one spacer installed on the machine plus another 9 gears and two spacers loose. The five on the machine were a 64T in the Back position on the lead screw followed by a spacer on the front position. The other four gears were another 64T, a 48T, a 24T and a 20T. This was set up for 0.0048" feed.