Holley 600 questions for 2x4

A little over a year ago I purchased 2 Holley 600 carbs from a member here. Carb numbers are 1850-11. Under the carb numbers are 1129. what does that number mean? Is it a manufacturing date?
Now these are vacuum secondarys and my plan is to use them on my edelbrock TL5 2x4 manifold.
Someone in the past cut the shaft and linkage on the choke and the upper plates flop around. So I tried flattening the choke plate to remove it but had no luck. What are my options here as I dont plan on using a choke. I am including pics of the cut shafts.
Next I have taken the the first carb apart and cleaned it overnight, washed the parts off and blown everything dry. The carb has 65 jets in the front and the rear is a metering plate. The bowls have what they are calling non adjustable needle and seats once its assembled.
I ordered quick change vacuum secondary housings with spring assortments and I plan on tying the 2 secondarys together.
This will be my first time ever using a 2x4 setup so is there anything I should do different as I put these 2 carbs together? Secrets?
Lastly I need to buy a new accelerator cable and will need ideas on how to mount the carb end. I plan on mounting the carbs sideways so my linkage will need to be mounted around the center left side of the intake. What have you used? Any pics of yours?
Thanks guys.
Rod
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