The plastic lamp sockets have 2 tiny little tangs holding them in. Plastic gets more brittle with age. Tweak those metal contacts if you want but... The more pressure the contacts generate the more likely a tang will break off a 50 year old socket. I had to learn this the hard way a long time ago. First one bulb inop, then a few weeks later a different bulb inop.
So if/when I service a rally panel I'll renew every possible aspect including 8 new lamp sockets and 8 Sylvania #2825.
I did once try LEDs in the 4 illumination sockets. The first 4 bulbs I bought at Ebay were a tad too long and bottomed out against the blue tint diffusers. the next 4 fit too loosely in new sockets. Something about their bayonet base was too thin, the plastic or the wire. They worked initially, testing on the workbench. Vibrations in the car caused them to flicker and/or completely inop.
Other members have reported the same while some have good results with LEDs. Good luck with yours