Get introduced to friends of the EEs you work with, and ask their help getting introduced to managers at your co-op company and at other companies. Ultimately, your solid co-op experience can outweigh your mediocre GPA, but you've got to lean on good professional relationships to help tip the balance. I have been telecommuting for more than a year now. I've been with my company more than four years and so have a good rapport with management. I also fly into my main office once every couple of weeks.
Phone calls replace face to face contact in most cases.
I dial into meetings and am able to participate without any problems. The fact that I show my face every couple of weeks does help in maintaining continuity. The arrangement has worked out well and everyone is comfortable with the levels of productivity I am delivering. Trust between the immediate manager and employee. You need to assure and reassure that your productivity will not be affected.