Wheel spacers, not sure which I need?

[TypeA]

Hi first time poster, tia for the help. I did do a search of the forum and google but couldnt find much on what wheel spacers I should be getting.  Heres the info Ive got, stock 2002 base Boxster with 17" turbo twists and the used tire/rim Id like to fit are sized 275 30zr 19 rears and 235 35zr 19 fronts.  From what Im told these were previously on a Porsche.   How do I know how thick a spacer I need?  I know I need longer lugs as well,  where do I find them that match the finish?   

 

Second question, the rims need the center caps but not sure the name of the rims,  can someone name the model?  Heres a pic:

 

 

 

Recommended seller and sizes I need would be great but any advice is appreciated

 

Edited October 13, 2014 by TypeA

[yuu1209]

SSR "WERFEN GT-03"

http://www.rd-tanabe.com/lineup/wheel/werfen/gt03.html

[TypeA]

Very interesting, thanks. 

[TypeA]

When filling in the first line to order these caps can anyone tell me what "PCD" means?

 

http://www.more-japan.com/SSR-Old-GT3-Center-Cap.html

[RFM]

PCD: Pitch Circle Diameter usually expressed in MM, it's merely the distance between the center of two diametrically opposite bolts (4 or 6 bolts wheels). For 5 bolt pattern, which is a little more complicated, PCD can be found by multiplying the center distance between any two adjacent holes by 1.701. An other solution is to draw an imaginary circle throught the center of all holes, the mesure the diameter of the circle.

[TypeA]

Thanks for the help :)