The following is an obnoxiously long technical explanation of why the Macintosh Classic II, LC, LC II, and Performa equivalents have a 10MB RAM limit. For most of this post, I use the Classic II as an example. TLDR: 1. Not enough address pins connected between CPU and memory controller. 2. Not...
This would be the primary concern with any Mac of that era. Even the original unibody Macs are prone to those issues. The one thing that might work in your favor is the LCII still being in a sealed box.