The only one's I was able to replace with LED's were the actual instrument cluster lighting. The other bulbs, which I thought could be replaced easily were actually kind of spot soldered to the base. It was actually easier to buy the correctly made one's. I spent an hour trying to solder those little leads to the base. I changed all of them. This was on an '85 300D. I might add the LED's really work well. I measured the current initially with the original bulbs and it was 700mA, the LED's were around 350mA, no more melted plastic.