I used to work at Mach Performance
www.machperformance.com and the centrifugal systems we used were strictly ProCharger (turbonetics and innovative for turbo systems). One of the main reasons is that their kits are all intercooled (or for Vortech and Powerdyne, aftercooled...same thing).
You can try and find a shop that will custom make an Intercooler for you. I am guessing that this will not be for "strictly racing" but for street use also. If that is the way you will be treating this vehicle, I strongly suggest air/air intercooler. There will be less maintenence and you won't have to worry about plumbing.
If you will be using for race only, then air/water intercooler will give you greater benefits.
You can buy universal intercoolers from places like Turbonetics, they sell Spearco, which is a pretty well known name brand in intercoolers.
For mounting ideas visit the pics page at the Mach Perf website. They have their ProCharged S-10 and Turboed XBlazer, along with several customer's rides. I worked on the Turboed XBlazer and 2 of the ProCharged S-10s that are on their site.
(I am no longer affiliated with this shop, and I do not believe they sell parts to the general public anymore. Just use the pics for design ideas)