I'm in the process of cleaning up a 9a that looked like it set in the back of an auto shop of about 50 years. When I bought it, I could tell it had likely been tipped at one point because the heads were broken off of both gear box levers. I wasn't super concerned because it was VERY cheap and I had a spare set of gear box levers from a previous rebuild a few years back. Fast forward a few months and I've got this new machine up and running sans QCGB. When I reassembled the gearbox after cleaning and repainting I noticed that in most of the lever positions the entire gear box binds up. I've gone over it thoroughly at this point and I'm pretty certain everything is assembled properly. The input out output shafts/gears spin smoothly. Both of the levers are a little difficult to engage and almost seem like they mesh too tightly and bind up the rest of the gear train when pushed all the way in. Everything I've been able to find makes it look like the castings/part #'s for these levers didn't really change, but it almost seems like they don't fit quite right. From what I can tell the levers are from the early 40's, I don't have any data on the machine they came from but they have a smooth unknurled top with a single rib that I've only seen on other machines from that time period. The rest of the gear box is from the mid 50's. I realize this is a pretty niche issue, but is there a possibility that the casting for these levers changed just enough that they're no longer compatible in that time period? I just don't see any other possible issues at this point and I don't have access to another set of levers to try. I really appreciate any input or ideas that anyone has. Thanks.