Re: temp guage
Yes any marine shop should be able to sell you a aftermarket gauge and sender kit(FARIA,TELIFLEX )In the kit you get a dash mount gauge, wire ,and a sending unit and in your case you'll use the bracket that bolts to the head and you screw the sender into the bracket untill it contacts the head.And by the way fix the audio alarm sender if you can I know I don't watch the gauges all the time.