Self signing ROMs

Has anyone installed self signed ROMs using the method described in a blog I can't post a link to since I'm a new member? The goal is to install a self signed image that allows you to install any image signed by your key to avoid the giant security hole caused by custom recoveries that don't check signatures.

Here's the overview :

Quote:

First: Unlock your bootloader. /data will be wiped. Second: Get a copy of the stock recovery.img for your device. Third: Grab mkbootimg from here and build it. Run unpackbootimg against recovery.img. Fourth: Generate some keys. Get this script and run it. Fifth: zcat recovery.img-ramdisk.gz | cpio -id to extract your recovery image ramdisk. Do this in an otherwise empty directory. Sixth: Get DumpPublicKey.java from here and run it against the .x509.pem file generated in step 4. Replace /res/keys from the recover image ramdisk with the output. Include the "v2" bit at the beginning. Seventh: Repack the ramdisk image (find . | cpio -o -H newc | gzip > ../recovery.img-ramdisk.gz) and rebuild recovery.img with mkbootimg. Eighth: Write the new recovery image to your device Ninth: Get signapk from here and build it. Run it against the ROM you want to sign, using the keys you generated earlier. Make sure you use the -w option to sign the whole zip rather than signing individual files. Tenth: Relock your bootloader Eleventh: Boot into recovery mode and sideload your newly signed image.

I have the 8" Tab (SM-T310) and want to try it. Anyone know if there's an official source of stock recovery images? I have the 4.4.2 update.zip from an OTA update I never installed (my tablet's still on stock 4.2.2), can the recovery somehow be extracted from that? Since I'm still on 4.2.2, I don't need to unlock the bootloader, right? Can I use Heimdall to put the new recovery on the tab?