Questions about the Ram Keeper

Hi everyone. Today I bought a boxed RamKeeper, complete with manuals and the external power supply. I have no idea yet when it will arrive, since it will be shipped from the US. In the meantime, I have a few questions about it. First question: from what I understand, the RamKeeper does not include any RAM. Unlike the RamFactor, it must be paired with another RAM expansion board. Can anyone tell me whether it can work with my Garrett Workshop GS‑RAM II GW 4201d 8MB card? Question no. 2: can you confirm that a TTL modification is required when using it with a ROM 03 IIgs? If this TTL is not modified, does it lead to malfunction or even damage? I’m referring to this modification: https://ae.applearchives.com/apple_iigs/ramkeeper/ramkeeper_iigs_rom_3_modifi.pdf I know that the RamKeeper allows installing two RAM expansion cards. I assume that’s correct, but let me ask anyway: with two RAM cards, does the system reach a maximum of 6MB? Or could two Garrett Workshop cards like mine be installed? I don’t think that’s possible, even though the 65c816 can address up to 16MB of RAM, because I know there are structural limits on the IIgs motherboard that prevent it. To go beyond 8MB many people install the Apple Squeezer, but I know that board bypasses the IIgs motherboard’s RAM management entirely. Last question (for now): the battery. I assume it’s external, like on the RamFactor. What type of battery does it use? Is the power supply shown in the photo enough to use it, even though without the battery the RamKeeper won’t act as a UPS? Thanks everyone.