I was replacing the ignition switch in my car & while removing the steering column a small pin on a spring popped out, (this is a 75 ) I looked at a 72 part I have & can't find that spring part there either.

could you tell me where it goes & what it does? I have added a picture.

Also I want to use a stock wheel, could I just swap the whole 72 coulmn for the 75 one, are there different electrical connections?

Almost looks like the horn contact button, but I don't have any parts with me to look at nor do I have the PET CD.

You have to see if your '72 has a pigtail coming out of the switches (early style). It will have a 12/14 pin connector on the end much like the connectors for the main body harness / engine harness. If it does ... no, it's not a direct swap.

I also believe that the ignition switch is different between late '72 - '74 and '75-'76.

Ignition Switches from Pelican Parts

Still not sure where the sping went but I installed the 72 unit and it seems to work fine (blinkers, wipers & ignition switch works)

Does the steering wheel still lock when the key is removed? If not, it may be in that system. You should be able to swap in the 72 column, and if needed, re-key the switch to your current key.