I don't think they map cleanly to the published specs. The printed specs are only loosely useful for comparison to begin with, since literally "Degrees per second" is a measurable number, and the reality is much higher. Lots of specs also change from when the documentation gets printed t0 the final game.
I remember reading or seeing somewhere that 360 degrees was represented by a number, don't remember if it was 24, 32, 36 or something else in the WC1/WC2/Privateer engine, for coding or storage reasons. Starting with WC3 the new engine used degrees. Just remember where I found that reference.
Well, generally speaking, the in-game values are simply 10x what the manual states - 6/6/6 becomes 60/60/60. However, some ships were also tweaked to some extent during testing after the manuals had gone to print, and therefore in some cases there are additional differences. This applies especially to Kilrathi ships in WC2, whose manoeuvrability was decreased in the game.