Back to GH though, wasn't there something about mounting versus installing? Something like mounting being more versatile and give less of an MV hit although the weapon would be more exposed to damage, something like that?
From the design file editing guide on the GH wiki(
http://gearheadrpg.com/wiki/index.php?title=Guides:Design_file_editing_%28GH1%29):
"Each mecha type (Battroid, Gerwalk, GroundHugger, etc.) has different base values, which are then penalized for the mass of the mecha:
Type: MV TR
--------------------------
Battroid +1 +1
Zoanoid +2 -1
GroundHugger -1 +2
Arachnoid +0 +1
AeroFighter -5 -1
Ornithoid -1 -2
Gerwalk -3 +0
HoverFighter -3 +0
GroundCar -1 +1
SE is the same for all mecha types -- it's -8 with no sensor, {Sensor Value} - 7 if one is present. If the sensor is mounted on the head, there is a further +3 bonus."
"MV is calculated as follows:
1. Start with a fixed value based on the mecha model. Three factors play into this: mecha type (Zoanoids are best, Aero Fighters worst), whether or not the cockpit is in the head (+1 bonus), and the quality of the Gyroscope (not shown in-game as far as I know, but can be found in the mecha description files).
2. Take the mecha's intrinsic mass (its weight with empty inventory and equipment) and divide it by 7.5t, rounding down. This is the intrinsic mass penalty. For example, an intrinsic mass of 28t modifies MV by -3, an intrinsic mass of 30t modifies MV by -4.
3. Take the mecha's inventory mass (everything that is equipped or carried in inventory) and divide it by a value that depends on the size of the mecha, namely (7.5t + 0.5t * size), again rounding down, then subtracting 1 if it is greater than zero. This is the inventory penalty. For example, a Fenris (size 4) will get the first penalty point at a carried weight of 2 * 9.5t = 19t, the second point at 28.5t, and so on.
There are further modifications in exceptional circumstances (Overloading, Gyroscope destroyed, ...), but this is how it works for a normal, fully repaired mecha.
TR is calculated in the same way, except that the targetting computer class is used in place of the gyroscope class, and that the fixed bonus for the different mecha types is different. For TR, Groundhuggers are best and Ornithoids worst."
* You get a -1 MV penalty for every 7.5 extra tons of installed stuff. But, for equipped stuff, the figure depends on mecha size (e.g., 8t for size 1, 8.5t for size 2, 9t for size 3, etc.). Note that Mounts and Hands weigh 0.5t.
* A gyroscope gets you a +1 MV bonus per level; so a Gyroscope +3 will chage a MV -5 to -3 or -2.
* Biotech mecha get a +1 to MV and TR.
* If cockpit is located in head, +1 bonus to MV and TR.