For some context, my car has been running like crap for a while. It would idle around 500rpms and fluctuate to the point where it dies if I don't press the gas. If I let off the gas around 1000 rpms or before it shifts to the next gear, it will die. I took it to the shop and they tell me I have a vaccum leak (which I know where it is) and I have a malfunctioning IAC valve. This valve is under warranty so I just gotta pull it out and turn it in for a new one. Queue problems:

So, my iac valve in my 2002 toyota highlander is bad. However it's located on the underside of the throttle body and held in with 3 Philips head screws. I cant unscrew it from under the car becaus the screws are so tight that ill strip them out if i try. The only way I can get to this valve is by taking the throttle body off but I can't get to the bolts for the throttle body. So I figured since I had to work the following morning I just sprayed some carb cleaner up and around the throttle body to clean any gunk that may be choking the airflow. After doing this, my car would idle at 2000 rpm and my idle speed is about 20mph. So I figured all that gunk I sprayed out may have settled into the iac valve and is causing it to be stuck open. Remember, I can't get the iac valve out without stripping the screws so what if instead I try flushing the iac valve out with some carb cleaner or pb blaster? There's a hole inside the throttle body that leads to the iac valve but I haven't sprayed it yet because idk if the gunk will drain out or if I'll make it worse by filling it with the carb cleaner. Any tips?