VRAM size patches not working in OpenCore - help!

I am squeezing every last drop of performance out of a Sandy Bridge HD3000 machine running Big Sur, and wanted to give extra VRAM a shot (beyond automatically set 512 MB).

During Catalina+Clover times, it was as easy as having this patch:

<key>Disabled</key> <false/> <key>Find</key> <data>0AAAACA=</data> <key>Name</key> <string>com.apple.driver.AppleIntelSNBGraphicsFB</string> <key>Replace</key> <data>0AAAAIA=</data> 

I'm running OpenCore now, and made the following patch:

<dict> <key>Arch</key> <string>x86_64</string> <key>Comment</key> <string>More vRam</string> <key>Count</key> <integer>0</integer> <key>Enabled</key> <true/> <key>Find</key> <data>0AAAACA=</data> <key>Identifier</key> <string>com.apple.driver.AppleIntelSNBGraphicsFB</string> <key>Limit</key> <integer>0</integer> <key>Mask</key> <data></data> <key>MaxKernel</key> <string></string> <key>MinKernel</key> <string>19.9.9</string> <key>Replace</key> <data>0AAAAIA=</data> <key>ReplaceMask</key> <data></data> <key>Skip</key> <integer>0</integer> </dict> 

However, that fails:

OC: Prelinked patcher result 10 for com.apple.driver.AppleIntelSNBGraphicsFB (More vRam) - Not Found

I've also tried WhatEverGreen's framebuffer-patch-enable + framebuffer-unifiedmem=00000080, to no avail.

What am I doing wrong? I don't want to patch system files :(