I'm guessing this is a track car? You might ask in the AX / racing forum, but I can't imagine that you will notice .1 degree difference in caster. I think that once you finish your mods, there will be some work needed on alignment settings to get things the way you want anyway.
What tires are you running? They need more camber than what you have?
There was a recent thread that went through some of the though processes and mods you mention.
Yet another tire/wheel choice thread...
That said it would be cool for you to document everything you do in this thread.
__________________
Gordon
___________________________________
'71 911 Coupe 3,0L
outlawed
#56 PCA Redwood Region, GGR, NASA, Speed SF
Trackrash's Garage :: My Garage