It took some time to procure the replacement parts needed for the Master Warning Lights. It was actually easier to order the whole assembly.
Although it is not the purpose of this site to show actual repairs, in this case the Maintenance Manual is lacking in practical steps for actually doing the job.
The mount for the light segments behind the center instrument panel seems to be permanently installed (there was no movement at all when grasping with a hand and there is no noticeable mounting hardware). Individual light assemblies (annunciator, diode block, and base) slide out of "sleeves" (6 sleeves, in this case). The annunciator and diode block come out forward. The base aft.
Some extra wires required removal from the base units of the replacement assembly. The pins came out easily with the red/white plastic tool. I used the Deutsch tool for all of them, but a Amp tool was ready for use.
(Rear Release Pins)
The annunciator and diode block come out together. The are some pesky plastic pins on the diode block that take some "convincing" to slide out of the sleeve. I treated all this gingerly to start with, but it was discovered that some firmness was required to remove and install some of these (a bent pick was a great help).
The bases came out by loosening two small set screws from inside the sleeve and bending some tabs on the outside. The bent tabs could be pushed back into position with just a finger. This cannot be bypassed when installing new bases in the instrument panel sleeve (the tabs will "not" catch the raised notch on the replacement base).
Each base has a stamp "A" through "F" on the back, but the bases are physically all the same. Working with the replacement assembly on the pedestal was quite easy...... working behind the panel, not so much fun at all. The first base out was the outboard upper (or "A") "FIRE" light base.
The securing screw and base tab can be seen.
Not every base required replacement. Some of the lights just needed the annunciator/diode assembly replaced. All three of the bases that did require replacement had at least one spring loaded pin stuck down.
This job was really quite a pain in the ass. Finding the right combination of annunciators to diode blocks was frustrating. The pedestal was strewn with chunks of parts everywhere. The stuck spring pins on the bad bases could be seen from inside the sleeve, so the ones requiring replacement where identified quickly.
757-200 AMM 33-16-02