HDS units require 1 xducer for the 2d ...and a second xducer for SideScan/DownScan ...

Transducer Shield and Saver makes tandem brackets for the TM...

Transducer Shield and Saver - See More Fish, Catch More Fish! - TS-LSS2-3D to fit LSS2 structure scan transducer

The Lowrance guys will be along shortly for suggestions ...

Rickie