This post from Camotli is roughly 35Mb, which is a bit more than e6's 20Mb limit. What would be the best way to make it compact enough for uploading? I'd rather not jump to framerate / resolution limiting...

You could try converting it to APNG. I've had at least one instance where an APNG ended up smaller than a gif. I don't know if it'll be able to get rid of 15MB, but it's worth trying at least.

You could try lossless filesize optimization. gifsicle -O2 or -O3 gets them both down to ~11 MB each.

It might be less hassle to just convert it to webm. GIF is old and unoptimized.

pocket_erector said:
It might be less hassle to just convert it to webm. GIF is old and unoptimized.

webm is lossy, and tends to not play well with the dithering or hard edges gifs tend to have.