I currently have a borg-warner 4spd manual in my truck. does anyone know what the 4th gear ratio is. i am dropping in a 350 but have to go with a th350 instead of 700r4 due to fianancial problems. I am trying to figure out what rpm i will be running at 60 mph with 235/75-r15 and 3.73 gears. with my manual i am around 1900rpm at 60mph.