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83 emissions control unit delete?

I have an 83 autox car that I'm trying to clean up the wiring on. The previous owner removed a lot of the emissions equipment and everything related to the cruise control. But he did most of it by just cutting wires. I've opened up the harness and I'm trying to pull out useless wiring. This brings me to the emissions control unit. I made a list below to try to understand what the unit controls. I used the pin identification scheme from the wiring manual.

I still have a few things I'm not very clear on, maybe someone can help. Ultimately it'd be nice to just completely remove the unit.

Section B of 1983 wiring diagram

A: Yellow/Green

Trailing ignition coil. (in?)
Still connected. Does the emissions control unit affect trailing timing? This also branches off to the tach, don’t know if the emission control unit is needed for tach output.

B: Black/White

Power from ignition runs through 15A fuse
Still connected.

C: Black/Red

Carb heater power
Already removed.

D: X

E: Orange

Throttle sensor
Already removed.

F: Black/Light Blue

Switching solenoid valve (out)
Already removed.

G: Green/Red

Throttle sensor
Already removed.

H: Black/Yellow

Starting motor (in?)
Still connected. What does this do?

I: Black/Red

Throttle sensor
Already removed.

J: Blue/Yellow

#2 water temp switch (in)
Still connected. What does this control?

K: X

L: Green/Yellow

#2 air conditioning relay (in?)
Already removed.

M: Brown

?
Already removed.

N: Brown/White

Relief solenoid valve (out)
Already removed.

O: Red/Yellow

Heat hazord sensor (in)
Already removed.

P: Black

Ground for emissions control unit terminates at X-13
Still connected.

Q: Brown/Red

Shutter valve (out)
Already removed.

R: Blue/Red

Choke and check relay (in)
Still connected. Is it needed?

S: Green

Vacuum control solenoid (out)
Already removed.

T: Green/Blue

Vacuum control solenoid (out)
Already removed.

U: X

V: Green/Black

Starting motor (in?)
Still connected. What does this do?

A. its an input. it gives the emissions box an rpm signal, which is just the - side of the trailing coil. the emissions unit does turn the vacuum advances on and off. it basically turns em off @zero throttle

H. off the top i'd say the EM box just gets a "start" signal, the ecu's in the efi cars get that too

J. they use water temp to kind of switch on the emissions system. the switch #2, is different from the one for the gauge

R. its really weird how the choke & check relay works, but i think its just switched power

V. not sure why they need 2 of these? nether are outputs

Thanks for the reply.

A. The vacuum advances have been removed from the car already. So I'm comfortable getting rid of this wire.

H. Comfortable removing it.

J. Whatever the input was used to control has probably already been removed so no problems there.

R. This one I need to do some more research on. I have found some info saying the check relay also carries a diode that keeps the alternator from discharging while the car is off. But I think this is a separate issue of the EM box. I can remove this wire from the box because It's just a switched and fused power wire. If I want to remove the choke and check relay I'll have to figure out how that affects the alternator wiring.

V. Same as H.

So based on this I should be able to just remove the emissions control unit completely unless I am missing something.

I was gonna ask about this as well. Seems the only reason I would have to keep it is that I want to keep my auto choke. I guess I'll have to find a new way of wiring it?

i'm not sure how the choke and check relay thing works, however on mine i removed it.

however i'm not running anything stock except the gauges and ignition, and lights