Questions/Comments:
Are you using antifreeze/coolant in the cooling system? I see rust coming out of your aluminum rad cap area.
Can you purchase a battery box (plastic or other)? Fumes and acid can spill into the car using an open/wet battery in your trunk area, so it is a must for everyones health and safety.
Is the CTS first on your list of repairs? I'm surprised the car would run with no proper connector/pigtail at the coolant temp sensor on your thermostat housing.
Definitely get all those exposed butt connectors out of the system, and replace with a proper connection/solder and heat shrink or heat shrink butt connectors.
Is there a gasket in the UICP (inlet pipe fitting to the turbo) where it bolts to the turbo? Red goop as a helper for pits can be OK, but if there is no gasket ....
Just trying to help you out here, no judgement.
I've had to do everyone of the repairs suggested above.