I recently got an 831 with a bad frequency converter, (it got wet and shorted everything) and I've been trying to find a replacement. I found someone who's selling a frequency converter in good condition, but it has a different NIIN. The one that this generator had originally had (01-477-0855) as its NIIN, and the one I found for sale has (01-587-6582) as its NIIN. I couldn't find the new one's NIIN anywhere in the TM, is this a new model of frequency converter (or is my TM maybe out of date)? If so, will it work if everything else in the 831 is still the older model?