Hi Bob, I also have the new springs as yet uninstalled & have been trying to educate myself about pad thickness for the past year before installing them.
I have come to the following conclusions thus far:
The factory installed 3 different sping sets according to curb weight of each individual car which is affected by such options as AC, manual vs auto tranny, model year, etc.
However, even knowing which color code of springs & rubber thickness of pads installed on your particular car might not help as the Olsen VR springs are said to be +/- 20% stiffer than stock & thus presumably will not compress as much thus making your car sit higher than it did with stock springs.
One member (who loves the new ride) returned his front springs to Olsen "who was kind enough to exchange them for ones 1" lower".
Bottom line, it appears to be a trial & error deal with lots of variables; I am strongly leaning toward identifying the PN on my stock rubber pads & starting with these pad heights recognizing that I may have to change later.
I would be very glad to read other opinions & ideas as I plan to do the spring exchange in the next few weeks. And FWIW, my '66 230 SL w/ 5 speed tranny (no AC) measures very similar to yours. F DS, 25 1/4"; F PS, 26"; Rr. DS, 26"; Rr. PS 25 3/4"; tires P185 70R 14.
While I have a parts book w/ PN's & price, Tom Hanson can provide more up-to-date info.
Regards & good luck to both of us.
-JP-