Wheel Spacers SOS!...stacking vs. solid one piece?

[hak134]

Greetings folks. Will be purchasing some Twists this week for my '72 SB as step 1 towards "Germanizing" my gal. 7/17's and 9/17s. The Backspacing on the 9's is 55mm. I DO want to go wider to fill my CCC fenders. I am looking for an alternative to gutting my rear end and converting my rear suspension from stock to 944. For example, I read that Lazarus added a 1.5" spacers to his backend with a wider fender. After doing extensive research on the Net I have found several retailers that sell "porsche" spacers and I am specifically referring to the "slip over/shim type spacers. NOT adaptors.

I found this quote on one particular Porsche parts store re. shim type spacers:

...Use individually or stack them for the spacing you need.

So my questions are:

Is is safe or unsafe to stack spacers to achieve my desired width? Or ideally should you purchase a solid spacer. (ex...2.5" in stacked vs a 2.5" thick spacer)

And is a 2 to 3" wide spacer safe? in other words can you go too wide for a particular spacer before switching to a wider trailing arm?

Thanks!

Hazen