rOk : Yeah, the lods are lower quiality versions of the full model (1.00 is the best, going down to 0.0001 I guess, the 0.001 is basicly a box with texxtures)
Look at some exisiting tanks (ODOL explorer the BIS ones, look at 'em)
For lowering the level of polys, I found a programs that does it, but.. it only works on VRML files (Virtual Reality Mark Up Laungue).. So it's useless.. But that shows a program can do it, so there must be one that can work with .3ds files (I've not really looked)
- Ben