From my 5.0TA, I'm told they are the same as the 21's.
Think Isosceles Trapezoid with the 2 front corners cut at 45 degrees 5" from the front. All the corners (6) are rounded. When in the lowered (bed) position, there is about .125" play, side to side. Don't know if the table tops are custom fit for each trailer or if they are all exactly the same.
Depth front to back, 29.25"
Width at the back, 34.5"
Max width, 5" from the front, 35"
Front width, 25"
After 2 months on the road the table wobble drove me nuts. I just replaced the table legs with the Springfield folks have been using. Would suggest you consider the same at build time, depending on what your table plans are.