Truck centers are the dimension from center to center of truck bolster, not the jacking pads.
This data is for units as delivered from the manufacturers.
Always refer to pictures of the unit to be modeled as many trucks are interchangeable.
The trucks were sometimes swapped by the Railroads or rebuilders.
27-00 note 1   DR-12-8-3000(Centipede)
32-03 AAR "B" 9'-10" DR-4-4-1000,DRS-6-4-660,DRS-6-4-750,
28-06 AAR "B" 9'-10" DR-4-4-15(BF)DR-4-4-15(SHARK)
30-06 GSC "C" A-1-A 11'-06" DR-6-4-1500
46-03 A-1-A pass 15'-06" DR-6-4-2000,DR-6-2-1000
32-03 note 2   DRS-6-4-1000,DRS-4-4-1500,DRS-6-4-1500,
32-03 note 2   DRS-6-6-1500,RS-12,AS-16,AS-416,AS-616
50-00 note 2   DRX-6-4-2000
37-06 note 2   DT-6-6-2000
28-02 AAR "B" 9'-10" RF-16
32-07 note 3   RP-210
22-08 AAR "A" 8'-00" S12
25-06 AAR "A" 8'-00" VO-1000
22-06 AAR "A" 8'-00" VO660,DS-4-4-660,DS-4-4-750,S8

Notes for BLW trucks:
1: trucks used on the "Centipede" special to this unit.
2: BLW used a variety of trucks refer to pictures for correct trucks
3: BLW hydraulic drive unit special trucks
AAR type "A" trucks used on switcher units had a whb of 8'-00".
AAR type "B" trucks used on road units have a whb of 9'-04" with GE traction motors and 9'-10" with Westinghouse traction motors.
A-1-A units used on BLW passenger units to reduce axle loading have a whb of 15'-06".
A-1-A units used on BLW road switchers units to reduce axle loading had a whb of 11'-06" with drop equalizers.
GCS "C" without drop equalizers the whb was 13'-00".

More BLW information
S.A. McCall