hello shermanmz, what have you tried exactly so far? it should be possible to get the .apk file directly from mozilla's servers & install firefox this way...

https://wiki.mozilla.org/Mobile/Platforms/Android#Download_Firefox_for_Android

Our recommendation for devices that don't have the Play Store is to use the Aurora build of Firefox as it self updates.

https://www.mozilla.org/en-US/mobile/aurora/

You will need to change some settings on your Kindle.

1. Go to the Settings screen on the Kindle Fire 2. Select the “Device” option. 3. Select “On” for the “Allow Installation of Applications” option.

Then download Firefox Aurora.

https://wiki.mozilla.org/Mobile/Platforms/Android You can get current release for either FF or Aurora via FTP from the link.

kbrosnan, essentially posted the same link you can get the Aurora builds from.