This Technical Bulletin introduces the procedures to upgrade the 429-001-523-101/- 103 and 429-001-532-101/-103 bellcrank assemblies to the latest configuration 429- 001-523-107 and 429-001-532-107 which utilizes corrosion resistant steel bearings. Bellcranks upgraded in accordance with this Technical Bulletin will not be affected by PART II of the Alert Service Bulletin (ASB) 429-15-21 Revision B. Customers should contact their spares administrator to obtain a one-time policy pricing on parts listed in the Required Material section of this bulletin. Operators who wish to purchase replacement bellcranks will be charged the retail price for the part and will subsequently be credited the difference with the policy price once the core return is received by Bell. The policy pricing will only be available for 18 months following the publication date of this bulletin. Applicability of this bulletin to any spare part shall be determined prior to its installation on an affected helicopter.