I don't think you have to rename any files to get the metric nomograph.
Just copy the folder 'TMO_ Metric_SpeedChart_Nomo' into mods and enable after TMO 1.7.
As for the periscope line - you don't need it. No need to line up horizontal line on waterline for correct range reading.
Photos I've seen of US WW2 periscope views seem to show no horizontal line.
Although if anyone knows better than me I'm sure they'll be along in a minute
If you still want the line back, have a look in the downloads section. I'm sure there are some periscope mods in there
Oh by the way, radar doesn't become available until mid '42. If you are early war that could be your problem