GM CAN line help please!

So, I’m currently working on a 2020 corvette C8 1LT that was in a front end collision that I’m having CAN 1 issues with. 

backstory to the car:
I bought the vehicle last summer to finish fixing and drive as someone had already fixed a lot of the problems and said “it’s close to done, it needs the steering, brake, air bag and  restraint module programmed.” I thought to myself no worries, he gave me the receipts where the modules were replaced, and I have SPS on a laptop at home. Bought the car and brought it home. 

I go to program the car?? No communication with any of those modules. I go through the folder of receipts to make sure I saw the air bag and restraint modules were replaced (found them) but also found where it had the main body harness replaced. I research the number and find it’s not for a 1LT but for a 2LT. That being said, corvette starting in 2020 had a different harness for every year as well as model of the car.  I think well that sucks, I’m going to have to order the right one. Call GM and find out they aren’t available but you have to order them and there is no ETA to get one. I’ve waited almost 7 months now on a harness with still no ETA. At this point?? I get diagrams and started hunting the differences. 

EVERYTHING else on the car works except those 4 things. I find that all 4 of those are on CAN 1 line, and the difference is hard to even explain, but it’s a complete disaster to unpin, repin etc. and some? I can’t even find.  Here’s the question for those who understand CAN lines. 

can I?
Run a set of two twisted blue and white wires (main wires) from the beginning module with the resistor to the end module with a resistor and branch off two legs for each module (blue wire and white wire) to all the modules in that CAN line that also includes the K56 serial data module to make this work?  
The way I ended up here is I found a video on YouTube from ScannerDanner showing GM CAN bus wiring and saw that the lines are a series parallel showing that the modules don’t have to go in and then out but just basically “leg off” to each module from the main two wires. Am I understanding this correctly?  If so, what I described should work correct? I’m gonna add a picture of the CAN 1 diagram I have for this car as well. The “X” is on the modules my car doesn’t have as it was a factory option my car does not have. 

Thanks for any insight!

Theoretically, what you are wanting to do seems plausible. If you can duplicate what should be, it should work. I don't see what you have to loose for trying.

I see only one option for a 2020 Corvette Info Bus diagram. Here it is, if it will help you build a harness.


Good luck! Keep us posted with any progress or obstacles that you have.  

Thank you for the reply!! I’m gonna give it a shot this weekend and see what happens. I’m going to have to download the file you put up and print it from my computer tomorrow! I have a hard enough time reading one that’s already printed out 😂 thank you and I’ll let ya know how it goes!