grounding means to branch panel
Greetings, I am upgrading a 100A QO remote panel in a detached building from 120V to 240V with 2-4 Al cable (all that was available locally) pulled from a 200A QO entrance panel. I gutted the remote panel and removed the bonding screw and installed a box grounding bar, drove an 8" ground rod and cabled it to the bar along with all the branch circuit grounds, separating them from the neutrals.
I have two questions: This leaves me with the insulated green conductor. May I ground it at the entrance panel as well as the remote panel? A journeyman electrician said that I could do this but I want a second opinion.
The other is, there is not available in either panel a means to ground the large #2 wire. May I bolt a grounding lug inside each panel case and install the grounding conductor to them?
Thanks for your help! Jim