One last thing to note is that the "T" in the stamped Marlin Crawler Serial Number stands for Turbo, which denotes that that housing originally had a 23-spline gear set installed in it. So much as that is concerned, it's looking good to be the original matched set.
tx_shooter- Please post up some pictures of the gears themselves, thanks for sharing and good luck moving forward with your project!
Regards,
BigMike
