I mounted my Kenwood TM-281A in the dash opening above the glovebox using a 'Sticky Pad' from Harbor Freight and a piece of 1/4" windshield wiper hose. This was to be a temporary mount until I could build an real overhead console but it is working out so well that I may scrub the overhead idea altogether.
The Kenwood has a front firing speaker and enough audio volume that I do not need an external speaker. The attached photos show the setup. I drilled a hole in the rear of the dash opening for the power and antenna leads and installed the 'stick pad' in the left side of the opening. The radio was placed on top of the pad and angled to make easy access from the driver seat. The 1/4" hose was pushed into the opening above the radio to wedge it down against the pad to secure it against the pad. The radio is held as secure as if I would have mounted it with screws!
The antenna is a 5/8 wave and is mounter on the tire carrier and the antenna wire is secured with clips and enters the vehicle through a grommet installed in the RH taillight housing.