The C in the serial number indicates it's a 3000 chassis (c430850) so it's probably a 3400. It should have the smaller, square axles and single reduction rear end. Same tractor as a 3000 in all regards except the front axle.
3400 was the smallest unit you could buy as a factory TLB.
Those 19-XXX numbers are the old system of Ford numbering - actually date back to the Dearborn days. Still helpful for ordering parts from CNH though. Most people will refer to things by the newer numbers if you can find them. Loader would start with 7 like 720 or some such. Likely just painted on the unit.
CNH shows 19-389 to be a 15" auto dig back hoe - used on a 3400. I don't know what the first K in the model # is either. (k5011k) Are you sure it's a K and not an *
You should ask the folks on the Ford Board.
Guys like Sean PA are very knowledgeable about those numbers.
The gurus here are quite good at helping you put points in a 6V 8N but not much help with Fords beyond that.
That 6X4 was kind of odd but good for loader work where you were doing a lot of back and forth driving. I put one in a 2000 with a blown tranny and then sold it. The pic below is of the shift pattern on them if that helps.
I wrote the pattern on the dash with a sharpie so I - and the new owner - could remember it.