I have connected my W.M M/550 VHF-DSC radio to my Garmin GPS-492. Just look at in/out wiring diagram for your VHF and GPS and connect accordingly (out signal of one to the in signal of the other and vice versa). It should work fine. I used a Radio Shack project box mounted on the aft cabin bulkhead as the junction box for both 12V DC power and signal cables. I went down thru the deck under the compass pedestal with the GPS Chartplotter cables.