from memory, dump the nand, get the cpu key (jtag/rgh), change the nand chip, reconfigure the resistors on the motherboard, build a 16mb image with xebuild with donor files using your cpu key/keyvault. what i am not clear about is i think the 16mb nand will still be read/written in 128kb clusters.
If you have the 64mb original dump you can use this as the nanddump.bin on xebuild to build the retail
I just did a 512mb -> 16mb jasper last week, worked perfectly with dual boot
