If you have not already follow this link....
http://www.rexnet.com.au/forum/index...howtopic=44189
These are a MRT/HYPERFLOW copy and bolt straight on to a MY99. You are dealing with an Aussie distributor as well. The only thing that you will have to do is trim around the intercooler shroud as you would with the genuine MRT item anyway.
Cheap.
J