AFTER ALL MY WHINING earlier, it ended up not being too difficult after all:
-six digit scoring
-single, six-digit high score
-high score is saved to AVox EEPROM at a different location than the regular Go Fish! high scores
-added (previously PAL-only) fish color changes: fish are darker at bottom and lighter at the top. Thomas' suggestion; this helps the fish be more visible - he suggested it too late for the NTSC version
-Eels are practically invisible (oops!) when they aren't flashing, especially on real hardware
-Should I add some kind of indicator to the title screen?
[EDIT: Forgot to mention - playtesting of this would be very appreciated! Especially looking at the fish colors, if they look good, and also general bug checking. I had to use a little more RAM and I'm slightly worried about the stack overwriting RAM, though I don't think it is ever a problem.]
As for how this will be distributed - well, I dunno. I do not want a general release of this, since the changes will only affect a very minor subset of players (namely, those, unlike myself, who can max the score at 9,999) and I don't want to be seen as trying to squeeze $ from collectors who feel compelled to buy one of everything. So, I am considering offering this on a cartridge for a reduced (i.e., royalties-free) price (possibly with a very slightly modified label) to anyone who can verify, with a picture, that they have maxed the score on a regular Go Fish! cart. Thoughts? Realistically, the only copies I will likely sell will be those that were specifically requested in the first place, but I figured since I did the work I might as well make an open offer.