Howdy Michael, I use code 83 on my 35n2 line, maybe a small bit of code 70 on funky sidings. I believe the 83 is around 25 lb/yard so that looks OK for me. Code 100 in 35nX is fine also. I have some dual gauge 2 foot and standard gauge with code 125 or maybe 148 which is OK for standard gauge.
Here's a (fuzzy) view of the dual gauge with the 2 foot siding reverting back to code 83.
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