Brandon -- you'd think so! It makes sense, right? If the dial says "Gear Down", then it's down-and-locked!
Except it ain't!
All the gear indicators do in a P-40 is tell you that the gear is extended. They do NOT tell you if it's locked.
Most gear systems have an over-center link, or a strut, or some external physical barrier that deploys at the end of the gear-down cycle to prevent it collapsing. The P-40 doesn't.
The actual locking mechanism is inside the hydraulic cylinder. An inner ram pushes a circle of teeth/cogs into crenellations, which lock the parts of the cylinder together, which is the only method of gear-lock.
Since this happens inside the cylinder, there is no way to put a micro-switch in it.
Here's a slide from my P-40 Groundschool, showing the parts.
The only way to confirm that the gear is locked down in a P-40 is to extend it normally via the electric pump, then swap hands and pump the hand-pump handle until it is rigid, then immediately move the gear lever upwards from the DOWN position to OFF.
If you allow the hydraulic pressure to bleed away within that cylinder, then the pawls retract from the crenellations, and you have no way of knowing about it until you touch the brakes and the gear collapses.