Go for it on the photos and if you need any others for your story let me know. I am very appreciative of the help and if that can help you back in some small way I am happy to help!
I'll be sure to attribute the photos (and anything else necessary) to you, of course - thank you for your permission!
So now I have the wires in the next step is take the IC out? Why am I taking the IC out? Because the arduino is going to replace it?
Once I have done that what next?
No, the next step is the probing - but first we need to do some sanity checks - read thru all of the following, so you know what is coming up, then start:
1: Verify your soldering connections - make sure you didn't make any bridges, and that the soldering job looks good; if not - fix it first (if you are worried about your soldering job, post a clear sample picture of your work here first, and I'll let you know what I think).
2: You did label your wires? If not, label them!
3: Make sure all the wires are separated from each other (none touching!) and that none are touching anything else on the board.
4: Take your meter (you do have a meter? if not - GET ONE) - set it to voltage measurement (you want a range of 0-10 volts at least) - if your meter auto-ranges, that's ok.
5: Hook your ground probe to the GND wire (pin 2) - use alligator clips or something secure.
6: Hook your positive probe (make sure it is in the voltage measurement plug on the meter!) to the VDD wire (pin 13), again with alligator clips.
7: Turn on the car carefully - put on a stand so all four wheels are off your work surface, but can still turn freely (and steering still works).
8: What does your voltage read? Make note of the voltage!
9: While on the stand, try using the remote to verify everything is still working OK - and that your "stand" isn't interfering with anything.
10: Turn off the remote.
11: Remove the positive probe of your meter from the VDD wire; hook it up to the RIGHT wire (pin 6).
12: Turn on the remote. While watching the meter, send the signal to turn the wheels right - read the voltage, and note it (also note: sometimes manufacturers reverse the order of the wires - so left is right and right is left - if you don't get a reading, try turning the wheels with the remote the opposite way, and see if you get a reading then).
13: Move the positive probe of your meter to the LEFT wire (pin 7) and repeat your testing and notes.
14: Do the same for BACKWARD (pin 10), FORWARD (pin 11), and TURBO (pin 12 - if your car has this option) wires - note the voltages you read.
15: Hopefully - the voltages you read on each of these tests match the read you got from the VDD wire.
If it doesn't - STOP HERE - and let me know what readings you got. Do not proceed. Proceed only if your readings are within 5-10 percent of VDD (there will always be some internal losses in an IC). If the voltages are the same - it means you can use the VDD wire (pin 13) as a probe wire. When probing, only touch it to the wires I have indicated, and not to any others (or any parts on the PCB).
16: Disconnect all the wires from your meter, and from the alligator clips (or whatever you used).
17: Again, make sure all the wires are separated from each other (none touching!) and that none are touching anything else on the board.
18: A good sanity check is in order - try your remote again, then turn it off if everything looks normal.
19: Now - take the VDD wire (from pin 13) - this is your probe wire.
20: Briefly touch it to the RIGHT wire (from pin 6) - did the front wheels angle right? Did they move at all? If not - do they still move with the remote? Do they return to center when you disconnect it?
21: Briefly touch it to the LEFT wire (from pin 7) - how about that?
22: Briefly touch it to the BACKWARD wire (from pin 10) - do the rear wheels spin in reverse?
23: Briefly touch it to the FORWARD wire (from pin 11) - do the rear wheels spin forward?
24: Briefly touch it to the TURBO wire (from pin 12) - do the rear wheels spin forward faster (note: if your car doesn't have a turbo mode, this may do nothing, or do the same as step 23)?
That should be it - if at steps 20-23 (and possibly 24) you don't get an action, try the remote (remember to switch it off afterward). If at any of the steps, you get the "opposite" action of what the wire is marked, it just means the manufacturer has reversed the pins (they also did the same on the transmitter - so no big deal) - just swap your labels around. If you don't get an action from your probe testing - but still do from the remote - that will be odd, and I am not sure what to tell you. If you don't get any action from the remote or the probe, that will be double odd (I don't make any guarantees on any of this - welcome to the joys of hacking).
Once you have performed the above steps, and know this is working OK - you can then proceed to the next step. But let's take this a bit at a time, ok? In these kinds of hack jobs, it is best to take it slow and easy - no rush - otherwise you make a mistake, and POOF - the magic smoke is let out of something.