Here I found my 49 torque tube in the shed looks like the dowel would be about 1/2 inch in and 7 inches for the back one . You should be able to see the round outline were the dowel pin is if you have an older tube .Before attempting to put a oakie in the tube after removing the first bushing check the old bushing and compare to the oakie inner and outer size .Measure the length of the oakie and measure the tube for how far down it can go .There is also a few u tube videos you can watch .