Mall 125 is all aluminum 1/2" drill from early 50s. Unbelievably, it came with a Jacobs Multi Chuck. I can remedy that. But I am not sure about what's in the Gear Case. I'd like to know cause there's a few of em I can get my hands on.
Does anyone know if this has an Intermediate Gear along with the Spindle Gear?
I was able to capture a print of this crude picture of the schematics. It shows a lone gear apart from things. I half assume that it could be the Intermediate Gear, otherwise obscured in the main diagram. It sure is beyond my abilities here. I hope someone more learned can help me here.
I can swap out the chuck but I can't do anything if it just has one gear.

How easy is it to take apart.  Most of those drills were pretty simple to disassemble.  You'd want to grease the gears and bearings anyway.

At a rated 500 rpm (see http://vintagemachinery.org/pubs/1183/25637.pdf), I would expect an intermediate gear train to reduce motor speed to output speed.

Bill, You replied right as I was modifying things to include this bad copy of schematics. But you're exactly right without it seeing it. If it's low speed; 500, it would have to rely on an Intermediate Gear. Thank you[ And thanks for that catalog.