Current status: 95/150 supporters
https://richardhaw.com/2019/09/22/repair-nikkor-ud-20mm-f-3-5-auto/
The 4th batch uses AI kit 20. To avoid repetition, I only list the AI kit against the earliest batch, following batches should used the same kit unless another one is specified, or the lens is AI
...Kit # 19 is available:https://kamerastore.com/products/search-Conversion%20kit%2019/