The CLW U-25B AAR Type B Trucks appear to have a slightly different INSIDE construction than the Kemtron AAR Type B Trucks used on ALCO RS-3s.
A brief comparison of ALCO and GE measured Lengths and wheelbases for these AAR Trucks shows only minor differences.
It seems unlikely that CLW made a modified set of AAR Type B Trucks that differs between RS-3 and U-25B Kits CLW made.