I am in the process of rebuilding my front end with poly and was also thinking of going to 17". The problem I have is finding rims, like the ones you have listed have almost a 6" backspace. You would have to use pretty big spacers to get the wheels sitting in the right spot in the wheel well. Trackhor you road race, so do you use wheel spacers? Did you ever have any problems with them? I was told not use any thicker than 1" and I would need 1.5" to make most 17" rims work, which greatly opens up the options.
I'm still building my Chally, so I don't know what I'll end up running for spacers. My current track ride is a Fox Body Mustang. I didn't need spacers b/c there is a plethora of parts for those cars including wheels that work without spacers. I did contact one of my vendors for Mustang parts and they assured me that the bolt on spacers are no less safe than bolting on the wheel straight to the axle. I have seen many of the Porsche guys running very large spacers on cars that exceed 200 mph with no worries.
Based on the research I've been able to to do thus far, I'll probably need a 1" spacer on the front The rear will work to my favor most likely only needed a 1/2" spacer. Both of which will be bolt on.
One thing I would do prior to using spacers is get some super high quality studs, like from ARP if they make them. Something else to consider is the spacers may not fit without some minor machine work. From what I've found the rotors are a little bigger on the hub bore than the spacers that may be readily availabe.
If at all possible make sure the spacers are hub centric. For those who don't know hub centric is where the bore in the center of the wheel keeps the wheel located on the rotor/spacer vs the stugs which is refered to lug centric.
It's my opinion that 1/2" or less spacers are safe for "slip-on" applications, where everything greater probably should be a bolt on.
I hope this helps.
Jason