[CentOS] google cloud compute with PEM file

Hi all,
     I am using the google cloud compute engine and we have a client 
that does not want to share their ssh keys. So I have been attempting to 
set up a PEM file for ssh access. Both the local server I used for 
testing and the cloud vm are centos 6.

I created a user on the cloud box, ran "ssh-keygen -t rsa" and took the 
defaults. I then copied the id_rsa.pub file to the local centos box, 
renamed it then made my test user the owner of the file. I then 
attempted to connect to the user I created on the google cloud box with 
the PEM file as shown below, but got the following error.

[test1 at pgpool1 ~]$ ssh -i /home/test1/my-key.txt upload at 815.677.151.45
Permission denied (publickey,gssapi-keyex,gssapi-with-mic).

Have any of you done this successfully before? Or know what the issue 
may be?

Thanks in advance