I think its an LDF7774ST. But, since posting this and spending 3 days taking all my dishwasher apart, digging out the air compressor, volt meter, 20 test runs, water all over the kitchen floor etc... I checked the where the drain hose connects to the undersink and found 2 cashews, some gum, and a couple pumpkin seeds. Running now... hasn't failed for the last 30 minutes. So basically it seems like a job I could have fixed with the removal of one hose clamp and a chop stick to poke through the block in 5 minutes.
Update:
So it appears to have been two issues. The line was blocked and then cleared. When I first disconnected the line, the y to the undersink drain was clear. After I blew the line, cleared that and drained the gunk into bucket, and reconnected it, other (now loose) crap then cycled through and plugged the y. All good now.
In summary:
After you clear the line, make sure you also re-check the y connection to the sink drain.