Meridian 508.20 to 508.24, how can I tell??

I recently bought a Meridian 508.20 that has been upgraded to a 508.24. Looking at the back of the player, there is a white sticker saying "24 bit DAC Installed". I don't want to open up the player to check, so besides that white sticker, how can I tell that it has been upgraded to a 508.24?

Also, when you send in a 508.20 to upgrade to 508.24, does Meridian upgrade the transport as well as the DAC?

Thanks in advance for your input,
I've spoken with a Meridian tech in Atlanta awhile back about the upgrade of .20 to .24, only change was installing the 24bit dac. If you pay extra, they install a new faceplate which is identical to original 508.24. I think the price was $695 vs $895, I can't remember.

Call Meridian and find out.
Send a mail to Meridian with the serial number, they will answer (besides, you may have requested the receipt for the upgrade from the seller...)