Lee,
Thanks for the info. I too have been thinking of doing the change - may try it next time a filter is changed as I just put a new one in. Mine never seem to last too long (as mentioned previously on this forum), getting only 6k miles or so. There is room for the filter in my coach (effectively the same as yours). I'd be more interested to know if the pipe down from the outside intake can be enlarged. (I believe Jim Nicholes did an extensive modification).
Michael,
that may fit, but in your coach if I remember the filter goes parallel with the coach and with the extra plumbing you have for the additional air intake it may be pretty tight, but then again you are master mechanic so I'm sure you can make it fit.
Jeff