I had the same dilemma. I bought most of the kit from Adam Cooper at Ace Performance. He supplies two brackets that will mount the LSA exchanger where the windshield washer goes. But then, you need to get a universal bottle and mount it somewhere else. Here in PA, a working windshield washer is necessary to pass state inspection, so I tried to make it fit with the reservoir in place, but couldn't.
Luckily, I used to run a RAMJET OTR CAI, and it came with longer top radiator brackets, which push the top of the radiator back to make room for the intake to slide in front of the radiator. Using those, I was able to use through the radiator mounts to mount the HX to the condenser, and with the top of the radiator tilted back, it all fit nicely.
While some think that it would get better airflow down low, I didn't want to risk putting it down there for fear of crap kicking up into it and damaging it. And when the fans are running, it really pulls a lot of air through. IAT's when cruising are pretty low.
I do also plan on installing an interchiller over the winter. If you want me to send you those brackets I didn't use, please PM me. I did hack them up quite a bit to try to make them fit over the WW reservoir, but they will still work fine.
'09 Pontiac G8 GXP, A6, Sunroof, MGM, #1664 of 1829
LS3, with LSA Blower, ACE ported heads, BTR springs and retainers, Straub trunnion upgrade, RCR cam, Kooks LTs/mids, Hooker SS MaxFlow mufflers.
BMR Rear LCA's, stabilizers, end links, front LCA bushings, rear toe links/trailing arms, Pedders Street II kit, including subframe and diff bushings.
Hawk pads, Brake Performance slotted and dimpled rotors, Russell stainless lines, Super Blue fluid.
Best 1/4 time, then- 12.52 @ 114.47, 1.94 60ft.