i installed a topmount intercooler on my MU (doubletake). the intercooler is from a ford teritory and also ford falcons,there is a little lag down low but it runs alot better up high,for the install i used a few things that i had lieing around but bought some silicone pipe joiners and a blow off valve (to fill the outlet in the intercooler)its not plumbed in,all up i think i spent around $130.
meterials i used are:
two stainless 90 degree elbows
one rubber elbow
two silicone joiners
3'' stainless pipe
the set up runs from the turbo towards the firewall then a 90 degree bend at the firewall over the tappet cover next to and parallel with the gas reserc pipe with another 90 degree bend into the intercooler.