Converting SF3 back to SF2?

Howdy! I'm working on an iPad music app that uses a soundfont, and unfortunately the one I'm using puts the app over the 100MB cellular download limit. I really like this soundfont and I'd prefer not to ruin the quality by reducing the number of channels or lowering the resolution. It seems that the best way to solve this problem would be to encode the SF2 to SF3 and then uncompress the SF3 back to SF2 on-device. (I realize it's lossy, but at least OGG is pretty close to transparent.) Unfortunately, I can't seem to find any tools that reverse the SF3 encoding process. Does such a thing exist? Thank you!