[SG & DS] Vehicle construction questions

Anyone have a ref from the book that says GMS/H and GMS/P don't have to
pay the multiplier for being turreted (2 x or 3 x weapon size class?). 
 
I know in DS they are just flat cap points, but is this also true in SG2
according to the rules text?
 
Someone brought up this point and I don't have an answer.
 
Plus in SG, an APSW (free) must be pintle, not under armour. How about
DS2 APSW? I think it can be presumed under armour right? (or at least,
no special rules for attacking unprotected APSW gunners exist IIRC).
 
Thanks!
 
Tomb