Using Amiga 500 Keyboards with Big Box Amigas

I'm trying to modify a standard Amiga 500 keyboard to work as an external Amiga keyboard for the big box machines. // Kindly sponsored by my favorite PCB manufacturer PCBWay! https://www.pcbway.com/ Amiga Keyboard Pinouts: https://sacc.org/demo/keyboard/a-keyboard.html Checkmate external Amiga keyboard case: https://www.checkmate1500plus.com/Products.aspx?id=353 Replacement Amiga 1200 membranes: https://www.sintech-shop.de/en/keyboard-membrane-suitable-for-amiga-a500-a600-a1200-please-choose/a-10308 Amiga 500 keyboard schematics: https://github.com/BleuLlama/AmigaSchematics/blob/master/A500_kyb_Mitsumi/A500_kyb_Mitsumi.png Crimping Tools*: US: https://amzn.to/3FKQCKW UK: https://amzn.to/49mnSWx DE: https://amzn.to/471zext MAS50 DIN connector*: US: https://amzn.to/3QtnD37 UK: https://amzn.to/3slzwjF DE: https://amzn.to/3FQ5asR MAS70S DIN connector*: US: https://amzn.to/40yfwao UK: https://amzn.to/40pLHJ0 DE: https://amzn.to/3svNW0F DIN to mini DIN adapter*: US: https://amzn.to/4