I have a 31' wood Trojan cabin cruiser. It has a Raytheon L365 fishfinder with an Airmar B44V transducer. I'd like to upgrade the fishfinder to one with at least a bigger screen, maybe even a color display, but I'd rather not go to the trouble and expense of hauling out and replacing the transducer. Are there better fishfinders that will plug in to the transducer? Thanks for any and all help!