Forget about installing OFW 3.55 and Recovery mode, it's really easy. Just download the latest Rebug 4.30.1, it can be installed over 3.55 kmeaw from XMB without having to go through 3.55 OFW and Recovery mode.
But before you do that, make sure you enable QA while still on kmeaw because you cannot do it once on 4.30. After you enable QA, update you multiMAN to the latest version and use it to make a NOR/Nand dump (in case things go south), then remove any original game disk from the drive and install Rebug 4.30.1 from XMB.
That's about it!
Regarding eboots, if you've been out of the scene for about half a year, then you should be OK, but if you had patched eboots and/or updates for 3.55, you have to restore the original unpatched eboots and/or original unpatched updates.