Here's a rough outline of what is on a RecMan page, above the picture:
Code:
Name Class [3/4 View] - [Close]
Tonnage Speed Draft Height [Send to TDC]
When you see a mod use "Length", they will usually change that RecMan page to display the "Length" text in place of the "Speed", and then put the Length figure into the the Speed line of the cfg file of the ship, such that "Speed=35" becomes "Speed=94" in the cfg file, which then looks like "Length: 94" in the RecMan instead of "Speed: 35"... There is a ~
LOT~ of work involved in that.