It may be just me but that throttle cable setup is giving me the shivers just looking at it
I would not use that type of cable on the throttle. I have seen that type bowden choke cable style break. Why not stop, take a step back and make some safety improvements while you have the cowls off.
As the others have said why not change the cable out to the correct length push pull throttle cable from Spruce or Mcfarlane with threaded ends on both ends to mount clevis or rod end fittings. You will find it will work much smoother than the choke cable style and especially if you drill the quadrant lever ABOVE the pivot and re route the cable to push rather than pull to advance the throttle. You will have to fashion a cable support bracket to hold the cable end near the REAR of the carb but that is not too difficult(add the mixture cable to it as well while you're at it). Vans may even sell one you can modify to fit this engine ( everything has to be modified to fit this engine!)
The mixture cable attachment is hard to see in the photo but looks to be a bugnut arrangement with a nyloc nut securing it to the bottom of the arm? This is a big no no in the Heat/Oil/Fuel environment under the cowling.The bolt is also too short with the nut at the end of the thread. Use a metal lock or better still castellated nut with cotter key.
I do use this type of cable and the bugnut arrangement you show on your throttle cable on my own mixture cable but mitigate the risk of cable breakage by using a mixture return spring from a Robinson R22 Helicopter. If the cable breaks or comes loose the spring pushes the mixture arm to full rich. Search for "Mixture Control Safety Spring" Part # A071-2 = Spring and associated hardware. It was a Service Bulletin for Robinson in 1984. https://robinsonheli.com/wp-content/...2/r22_sb41.pdf
Flying a H2AD in an RV6 for 14 years and luvn it.