Welcome gullchaser1961.
May I please suggest that you go to the "photos" section and see what you can find that other 170 have done.
You may, after looking things obver, come up with a better idea. If so, please share pictures.
My son and I listened to others and went to best buy, purchased the unit we wanted with a warranty. It was NOT a marine rated unit, but 5 years later it is still working.
Vic in Osprey FL
2005 Triumph 210 CC with a collapsible radar arch on a Rolls Axle trailer
Boat Name: Irresistible