cluster wiring

[sr vegas 240]

first time 240 owner it has s14 notch top sr in it thats how i got it i know wiring is a mess in this car by who ever did the swap. wires off the ecu just exposed everywhere some taped up some just left hanging its scary, 12v running trough a small switch for electric fans no relay or a fuse, that was all fixed what my questing is to you guys is how to get the oem tach working with the swap here is what i know and have
s14 sr20 in s13 chassis
sohc cluster i know i need to get dohc cluster to get rpms to work
i also have autometer 9117 tach adapter
when i wire the tach adapter where will i run the signal wire to
i know that from the ecu to cluster i need to run a wire from pin #7 which is tach signal output but where is the ecu input from tach adapter.

ive searched for days now and thats all the info ive found any help is appreciated

[sr vegas 240]

bump anybody know

[sr vegas 240]

I also just learmed that its a non jdm ecu s14a so rpm signal would be pin #2

[sr vegas 240]

The more I look around this car more scary it get according to the wiring diagram all the injectors r miss wired ecu pin out for injector no 1 is wired to no 4 wtf when I test drove the car ran like a champ no misfire issues or nothing how could this be anyone any help please idk if I should try to fix the injetor wires or leave it maybe I'm missing something runs fine