a smaller pulley aint cheap and easy power????
a 3.5 is one size smaller than the 3.6. he already has the 3.6. the boost difference is barely going to be noticeable if any.
if anything, take a few different pullies with you when you go get it tuned. see what works the best...
hell, if you really wanted to feel what the 3.6 feels like run some race gas in it and see whats up. but then you gotta press the 3.8 back on if its a press on.....