On the ebay kit the shorter pipe goes to the plenum, this is very short so if you use it as a short ram then the filter has to sit under the strut brace.
The filter is also very small and is only rated to 170bhp.
If you also see the quality of the pipework in the flesh you will see why it is so cheap, The joiners also are plastic.
Sorry guys but you get what you pay for, we were offered these and buying in just volumes of ten units we could buy this kit dor £18 each, says it all really.