HOW TO MAKE IT WORK-ISH - THIS IS NOT A FIX:
dmesg shows the sd card is sda1 now.
in /dev there is no sdcard folder.
fstab points to /dev/sdcard/sd1.
I'm guessing in this firmware the device id changed. I changed the fstab to point to /dev/sda1 and manually kicked off mount -a from ssh. The SD card then mounted to /sd and when I went to Manage Modules on the web interface it gave me the option to install to SD card.
Now I'm not great at this but I see some stuff that needs to be fixed:
1: sda1 instead of /dev/sdcard/sd1.
2: sda1 seems to randomly di