I have just completed the M50 intake manifold conversion onto M52 2.8 engine on my Bertini GT25. I decided to convert the manifold rather than use the extra hose method. It was fairly straight forward to do as long as you have something like a Dremel tool. If i did another i would only bolt the backplate on at both ends because you dont much room left after cutting the hole for bolt holes at the sides. Make sure you seal it up well because you dont want vac leaks. I made up a length of angle as a bracket to mount everything to and re used the manifold mounts from the M52. It is a bit of a fiddle to switch the manifolds over so give yourself about 4 hours if you have a go. The results are very good i was expecting to have lost a load of low end tourque but it is not bad, up above about 4500 rpm you really notice the difference which is probably helped by the airbox fogging which i had already done.