Looking at a Basket case but the numbers don't seem right. Looks to be a late 60's frame and unit construction motor. The frame has the same number stamped on it as the engine. Frame stamping are low on the side, not as my 500 is. T120R 60058 are the #, can't seem to find a chart that shows that number. can't get pictures till next week. I will keep looking for the year.