Deane Kidd put this mod kit together for me years ago. It was an official Tek kit p/n 040-1038-03. Auction also includes all the original 492/492P manuals: OP, Service Vol 1, Service Vol 2 and Programming along with the mod sheets/documentation.
This kit includes everything (Deane was meticulous) including all the cables, screws and cable clamps.
I never installed it, I sold the 492 a while back.
Please send me a PM if you are interested