i got new brake cylinders for the front of my 69 barracuda and when i went to put the driver side on, the cylinder won't fit. i talked to the guy i got my car from and he told me he replaced the hole housing and drum with another year but counldn't remimber what year. the lung nuts come off the same way as the passenger side. and the back of the cylinder is squaress. or can i just swap out the rubber and use the old one thats in it.