Steve, It's interesting doing the research on the "Transition" part of Ives, Lionel-Ives, then strictly Lionel, over the 1931-1934 time frame. Some parts are from the Ives inventory, some were from Lionel, and a combination of both. Most of these were made in Bridgeport, CT, at the old Ives factory, and ended in New Jersey at the end of production. When you compare the early Ives motors, they are narrower at 5/8" wide, and a smaller spring, and threaded key. The Lionel-Ives, & Lionel motors measure 3/4" wide, with a wider spring, and the box shaped key shaft. An interesting characteristic with the boilers on the Ives 1506 (Non battery, or headlight, and the Lionel 1506's is 4 round dots just in front of the cab. Lionel apparently kept the dies/tooling for the boiler, to make the Ives loco, and the Lionel issues. They only created a new frame, to make the 1506L, for the battery opening, but used the same boiler. Then when you throw the "Winner" locos into the mix, you have the 1015 & 1035 locos, but Powered units, there are two different boilers. The 1015 has "Winner" plates directly behind the Steamchest, and under the windows of the cab, NO 4 round dots. The 1035, added a headlight, and used the boiler stamping of the 1506's, and had the 4 round dots in front of the cab. Researching thesed locos, mostly windups, plus the later powered units, it makes your head spin...LOL. I have been studying all these bodies, and the comparisons from Ives to Lionel. I have to get in down on paper, then create a document, when time permits. It's fun though.
Check your boiler, if it has the 4 round dots just forward of the cab. If that is what you have, because of the motor windup key, you don't have the 1501, but the Lionel 1506(M), which is the Mickey Mouse version, without any headlight.