All right I'll give you the answer you want.

No, for god's sake, do not email yourself the ROM. The cyber police will no doubt find you and sentence you to twenty years of no internet access.

If you absolutely have to do it, make sure you triple-encrypt it with AES256 first, and change the filename to "my.girlfriends.tits.jpg" before sending it. This is the only way to be safe.

Btw you should put on a helmet before exiting your house as well. You know, just in case.

(SPOILER)It is also completely ridiculous that you insist on using e-mail for this while at the same time being so extremely worried about being found out, when the USB STORAGE DEVICE I mentioned earlier would be completely impossible for any of the EVIL GOVERNMENT INTERNET DUDES to find out about.