Thanks for the help, Alex. I'll try to help him get going if this doesn't do it. You're right, I forgot that it doesn't have file-naming rules, only folder naming ones.
That said... It depends on his needs which way would be best. If it was me... I'd probably strive to use the SDHC card directly as a handheld, rather than using the hard drive folder then manually copy via another mechanism method. Simply because of this exact thing:
In addition a hard drive location is not limited to the size of your flash memory card(s). If/when preferred you can have more than 32 GB of files and copy only a selection to the memory card.
The benefit of using the card directly is actually
this very thing as well. If you add the card directly as a handheld device, then MC will "know" how much space you have to work with. Instead of "pre-creating" all of the files you need, and then manually copying them all over to the card, you can set it all up as part of the sync. MC will automatically convert new files as needed each time you sync to the card.
If everything fits after conversion, you can just select all of your music media in the Handheld Sync dialog, and it'll always sync everything over. Conversions can be handled via the conversion cache, and the only thing you'd need to do to "update" the card is plug it in, open MC, and hit "sync" and all your new stuff will go right over there automatically. And, if you run out of space on the card, you'll get warnings from MC, and then you can deal with it.
If everything WON'T fit after conversion (I'd never even get close, even with a 32GB card and 128k CBR files), then you can use the powerful Smartlist features of MC to make a randomly changing "set" of songs to sync over to the card each time you sync it. You won't have everything, but you can be pretty clever.
Alternatively, especially if managing the file names themselves is very important to you, it might be better to use Alex's suggested method. This would let you use the handheld sync to a folder like a "cache" of pre-converted files, which you can then go in and move over to the card yourself however you'd like. I'd probably rather give up on the file name thing and use what MC does itself (while simultaneously begging the powers that be for the ability to set a filename rule in the Handheld Sync options, like you can folder rules). It would be much easier to do it this way over the long term.