1986 JEEP CHEROKEE Steering Problems

I BOUGHT THE CAR AND DROVE IT HOME ON NOVEMBER 13, 2013 WITH THE INTENTIONS OF MAKING A VEHICLE TO USE IN THE WINTER FOR BAD WEATHER OR VERY BAD SNOW. HERE ARE ISSUES I FACE. THE SPEEDOMETER GOES CRAZY ONCE I REACH SPEEDS OVER 35MPH. IT GOES WELL PASS THE 85MPH MARK AND BACK DOWN TO 15MPH AND BOUNCE ALL BETWEEN. THE VEHICLE IS SO OUT OF ALIGNMENT ITS DANGEROUS. ALL THE FLOOR BOARDS HAVE BEEN RUSTED THROUGH ALL THE WAY BACK TO THE SEATS. THE FRONT PASSENGER FLOOR BOARD IS 1/2 MISSING, AND ALL FLOOR BOARDS ARE EXTREMELY WEEK.THE DRIVER SIDE HAS A POP-RIVETED FLOORBOARD IN AND IS VERY STRONG BUT THE BOTTOM HAS BEEN RUSTED THROUGH SHOWING THE BOTTOM OF IT,AND THE SIDES HAVE RUSTED THROUGH WHOLES. WHEN I SAT IN THE DRIVERS SEAT TO REPLACE THE RADIO,I WAS FORCED TO REMOVE THE CARPET TO INSTALL A...