Let's see how brave we are;
What STUPID/DUMB mistakes have you made in building or maintaining your Cobra.
I'll start off from my build, trust me I have more than this one.
Installed the motor without first installing the flex plate. The only motor/engine swaps I've done (old time) bolted directly to the trans, the flex plate was a new addition. The instructions told me to install it, I just got in too much of in a hurry.
After reinstalling the motor I realized I forgot to install the pilot bearing.
one in, one out, one in, one out. STUPID.