The motor and chuck assembly can be pulled up and out.

Be aware of the speed selector (first picture) which is slotted onto the motor and chuck assembly as you remove it.

Remove the electrical connections. The colors are marked on the motor so no need to remember which side is which.

The electrical connections are spade terminals with a little locking piece on the front (non flat) side of the spade. Push the lock to the back and pull the connector straight out.

What's remaining is the motor and chuck assembly (third picture).

The chuck can be removed with a hex key, I didn't go that far in the disassembly.