This is a rather neat solution and perhaps one that should be taken onboard by the manufacturer. Winnebago use a plastic surface mounted air intake on most Mazdas - T4600 etc. This can be seen in the picture below. Graham Smart of Beechworth simply went out to Whitworth Marine and bought a very good looking marine scoop vent. This has improved engine breathing immensely according to Graham and he feels that it looks a lot better too.