GPA Engineering Pty Ltd - EIDA Business Directory Go back to directory. Add to Address Book. GPA Engineering Pty Ltd GPA Engineering Pty Ltd Contact: Sean Flaherty 121 Greenhill Road Unley South Australia 5061 Australiawork Phone: 08 8299 8300home Website: GPA Engineering Email Us JavaScript is not enabled. It must be enabled in order to send a message. First Name:Last Name:Name:Email address:Subject:Message: Send WordPress › Error There has been a critical error on this website.Learn more about troubleshooting WordPress.