No you can do this repair just fine. But there are some thing to know.

1. You are going to need a service manual and GE does not let its tech info go outside of its authorized tech personnel. See if you can get GE to send you one since you are an owner, and if not see if you can secure on from the web, and if you have to pay a nominal fee to down load go ahead, its worth the money.

2. These machine diagnostics are notoriously unreliable so replacing the motor may or may not fix things. Not sure which nut you are trying to remove but make sure it is not reverse threaded. GE does that a lot.

3. This model washes great but it is very unreliable and if you have gotten 10 plus years of use out of it without a major repair you have been very fortunate. But it is near the end of its expected life (unlike mechanical models these high tech, board controlled machines just do not last like a basic no frills top loader and GE has way over-complicated this model). So you may want to consider replacing it rather than fixing it.

Good luck!