LEDs by nature are polarized, meaning you need to have each lead installed to the correct terminal (I assume you know this but stating anyways for continuity). I've seen some bulb makers claim otherwise but I wouldn't assume. When you go to swap the bulbs, they're in those little removable plug things, which can be inserted to allow for both polarities (meaning there's a 50/50 chance the LEDS won't turn on). First and foremost, I would switch around the ones that aren't working to see if that might fix things.The 74s I bought from 2 different stores didn't fit right, as they were too wide/large. I could force them into the socket connector, but it spread out the plastic sides such that I couldn't get the connector back into the back of the circuit board. Took them back to the store with the factory bulb, and it looked like #2723 (I think) was the closest size match. Wattage was a tad higher, but nothing major. The 2723s fit perfectly and worked great once I put it all back together.
@323 - this seems to be inline with that I've heard, so I won't generalize and say that 74s are wrong. I think it really does depend on the quality of the bulb you're buying. Good to have this info, I may look at the bulbs you suggested to replace the cheapo eBay ones I bought.Also, I didn't have fitment issues with my 74's. I suppose the size of the base varies by brand.
I do remember having to bend the prongs on the bulb seat so that it was a tighter fit for a couple bulbs that would want to go in and out. Other than that, no issues to reportI only changed the four illumination bulbs (two smaller and two larger). I initially saw all of the others, as well as some of the open, unfilled slots in the back, but it makes sense now why those don't really need to be replaced unless they go out.
@323 - this seems to be inline with that I've heard, so I won't generalize and say that 74s are wrong. I think it really does depend on the quality of the bulb you're buying. Good to have this info, I may look at the bulbs you suggested to replace the cheapo eBay ones I bought.