Rick, the long frame slide is approximately 5/64 of an inch longer than the short frame receiver with the entire difference being in the length of the receiver ring from the face of the breechblock forward. The toggle train should be the same in both the long and short frames. This is according to "Lugers At Ramdom" by Charles Kenyon, page 23.
Wes, thanks for the tip. <img src="graemlins/beerchug.gif" border="0" alt="[cheers]" />