I'm pretty sure that the LC475 has 4MB RAM soldered onto the motherboard, so 132MB is the limit.

I have that and it is an impressive sight. I got my 128MB SIMM from a Sun Cobalt server. They get hot too.

They are big fellows and the block the heatsink on the CPU, if you've managed to beef up the processor to 68030 33MHz or beyond.

My plan is to boot to a system with a massive RAM disk (say 64MB) use an AppleScript to copy the System Folder across to the RAM disk and reboot from the RAM disk.