Information about BMC air filters

Hello, just started putting my BMC air filters on my 1991 TS. The kit came with this flexible aluminum tubing that goes inside the factory air hoses and then connects to the filters. The problem I am running into is that the flexible tubing will not fit inside the stock air hoses the diameter is bigger than the ones that connect to draw air from the sides of the car. So my question, is are these aluminum pipes really even needed? I have found a way to mount the stock air hoses directly to the filters and mount them down. All the pipes do is add a foot and a half of ugly black tubing. Anyone run into this before? I will post some pics when I am done, just wanted to make sure I am not missing something here.