8&3/4 axle fitment problem

I cannot get the axle (tried the dr side) to slide all the way into the housing (~3/8 or so). its an A body confirmed by Moser A body housing, Dr diff axles but I tried some SBP 8&3/4 axles & same thing. it sounds like the end is hitting something solid in the pumpkin, it is a 5:57 welded spider chunk in the stock car. I did shine a light in & I can see what appears to be a solid round area with maybe a small hole in the center. thank you for your time. RR