Kubota BX2370 instrument cluster repair

Kubota BX2370
wiring diagram
https://www.manualslib.com/manual/1774272/Kubota-Bx2370.html?page=321

water damaged instrument cluster discontinued part #K2731-62510
main problems water from leaky lens had collected in bottom
- lens seal compromised
- galvanic corrosion to constant 12v pin #2 destroyed pin and damaged connector socket
- corrosion to other pins and socket
- trace from switched 12v through diode to hidden trace under stepper motor completely destroyed by corrosion leaving different parts to right of stepper motor [bottom view] including T720M05Q 5v regulator without 12v
- stepper motor armature seized with powdery rust

instrument cluster pops out by inserting two screwdrivers between cluster and cowling with a little pry and pushing back of cluster to release clip tabs/cluster

most of the ic's are obsolete/no longer listed making it difficult to know what you are looking at
replaced missing pin #2, cleaned and tinned other pins using acid flux then cleaning off flux and wiping pins smooth
inserted sewing pins with heads cut off bent in u shape to prevent being pushed into female connector in pins #2 and #9 to assist in electrical connection to damaged female connectors
opened cluster by removing four phillips screws at back and carefully prying off lens
general inspection/clean with alcohol and dry
connect +12v to constant 12v pin #2 and switched 12v pin #9, ground to pin #16 > generally explore for voltage, especially left pin T720M05Q 5v regulator
[removed T720M05Q 5v regulator to determine whether 2.5-3.1v output was shorted component or no source voltage to left pin > regulated 5.04v to 400ma load when 12v power off instrument cluster board]
[removed 14v varistor S14K14 to verify not shorting with applied voltage]
sourced where 12v for left input pin T720M05Q 5v regulator came from and found switched 12v from cluster pin #9 went through diode to large trace which went under stepper motor but fed nothing to right of stepper motor > after testing with reduced currents permanently installed jumper from anode of diode to trace connected to left pin T720M05Q 5v regulator > now supplied regulated 5.04v / everything lit up
opened stepper motor to remove powdered rust seizing armature > this requires proper procedure
remove top case of stepper motor and before doing anything else note/mark rotation position of armature [important to have gauge return to 0 after fix]
remove/lift and clean blue gear between armature and gear to gauge needle
lift out magnetic armature [having previously marked rotation position] and remove powdered rust attracted by magnet of armature / powdered rust on metal around armature
lightly air blow out other powdered rust [don't use magnet which might magnetize metal around armature]
reassemble armature noting marked rotation position and blue gear insuring gauge need is at 0
replace top case of stepper motor [to prevent losing/damaging parts]
reinstall in kubota and start varying engine speed both to verify functioning and to collect more powdery rust on armature > found armature/gauge needle quickly seized requiring repeating above removing and cleaning off powdery rust on magnetic armature [more than once]
remove silicon lens seal and replace with new seal [used rtv which allowed repetitive opening of cluster]

other than scraping tinned pins #11 and #12 for intermittent turn signals, that pretty much restored the instrument cluster [probably similar for other water damaged instrument clusters].....