This article is issued to bring to your attention that in case the integral lighting of the Standby Attitude Indicator is inoperative, you have the possibility to replace the lighting block.
The history of Standby Attitude Indicator removals show that the indicators were replaced several times to replace the lighting block in a repair shop. This is not necessary because there is a removal/installation procedure in the AMM to replace the lighting block, refer to AMM 34-24-01. Costs will be saved by performing the removal/installation on the a/c.
The only discrepancy is that the lighting block is stowed in the Spare Bulb Stowage Box but that it is not listed in the IPC. A supplemental IPC may be added to the official documents by your company. The p/n of the lightning block is H342AA55. See picture below. Tip supplied by Marc.