Remove directory from Google Cloud Compute Engine using serial console [on hold]

The storage on my Google Cloud Compute Engine Instance (inadvertently) got completely used up. I can no longer SSH into my instance. I have increased the space on my instance, but it still will not allow me to SSH. My VM operating system is Ubuntu.

I have tried two things:

1.) I have tried creating a start script to remove a large directory to clear up some space. Under “custom metadata” I have set the key as “startup-script” and the value as

#! /bin/bash

rm /home/myusername/dir-to-rm

I save and reset the instance, click “connect to serial console”, but I still cannot SSH.

2.) I have tried to use a startup script to set a login username and password for the serial console by using the same method, but with the following script:

#! /bin/bash

sudo useradd tmpuser

echo 'tmpuser:password' | chpasswd

Neither of these methods have allowed me to SSH back into the VM.

Any help would be greatly appreciated.