I just got my 289 fired up for the first time in 10 years and mine leaked from the push in dip stick also. I drained the oil and the pulled and cleaned the end of the tube up good and applied a bunch of permatex. I pushed the tube back in and added a nice thick layer of permatex around the tube on the outside also. Let it dry good for a few days then dumped oil in again. Fixed that leak, but now it just seeps through between the pan and the plate that is rivited to the pan
! It ant as big of leak but still leaks. Ill have to look at maybe droping the oil pan and just welding everything up solid!
Just letting you know that it may not just be leaking from around the tube.