digital speedometer stuck at 0

Did you check for voltages present when you unplugged the speed sensor, to test the continuity of the sensor and supply voltages from the pigtail end? Perhaps you forgot to plug them back in after testing...it can happen.

perhaps the big boots hitchhiker kicked way up into the dash, disconecting a few connectors?

I pulled out the tranny sensor and manually spun it and checked to see if it made a current, which it did. Then i disconnected the back wheel speed sensors and had a friend spin the wheel and each one came up with a current. And thats about where i gave up because i couldnt think of anything else.

so electrically, we're golden down at the speed sensor...yay....now at the dash we should take a look at the connectors that connect to the back of the speedo, make sure they are plugged in and havent jiggy-jigglety jigout of postion...after all this is as exotic as a ford.

cluster replacement needed no doubt, diode brakedown

just replaces the voltage regulator, and that did no good, though never hurts to have a new one... have not had a chance to rip out the dash yet and prob wont for a while, so it has come down to: 1 wires from the regulator 2 something behind the dash and 3 possibly a fuseable link?

Na thats not it i pulled out all the sensors and tested them and their connectors and put them back. I was driving yesterday and hit a large bump and the speedo started to work, only when i went back out a few hours later it was back to not working again :/

aha!....that's it just aha, well, there's more to the aha, being in that power was restored to the sender part! yay....break out the confetti, the party pops and a pinyahta! wowee woowee~

pulled out the cluster, the printed circuit board is shot. any one know if there is a place to take it to get fixed or where i can find a new one?

you can find another Lincoln like yours in a picNpul or U-pull...wear some boots and sunglasses and have a hike lookin' for it~