Guardian Credit Union » Member Directory Go back to directory. Add to Address Book. Guardian Credit Union Guardian Credit Union Contact: Denise Wendlick Work 1025 Milwaukee Ave. South Milwaukee WI 53172 work Work Phone: 414-546-7450 ext. 2328work Work Fax: 414-762-9301workfax Work Email: dwendlick@guardiancu.orgINTERNET Website: http://www.guardiancu.org