The only RELIABLE way to do this is to have a GPS and Loran right next to each other as you navigate to your TD's with the Loran and then make a new waypoint on your GPS. None of the tools for converting are going to be very accurate.
That said, here's the USCG tool for conversions. Use at your own risk.
http://www.rdc.uscg.gov/rdcpages/soft-posaid2.html
That said, here's the USCG tool for conversions. Use at your own risk.
http://www.rdc.uscg.gov/rdcpages/soft-posaid2.html