One of our cats has a similar routine to Bill's--When I pull into the drive he will either come walking over or be waiting when I open the truck door.  He then has a procedure we have to go thru but he is particular on how it's executed.

He has to "give me the roll" as I call it, but...

1. He has to do it on the earth, not the driveway.

2. I have to be a certain distance from him or he will re-position himself to the correct distance

3. He then lays there until I rub his belly which most cats don't seem to care for.

When the routine is complete he dashes to the front door to go inside.

I have gotten to the point I get out of the truck and just stand there to let him position himself, do the roll and then I rub his belly--saves time.

He is the only one of the three that goes outside.  He not only pushes the door open to go out but can open it and come in.

They really do become part of our lives.

Very sorry for your loss.  As many others have expressed, I've been there.  Helps to focus on the good times, and how good a life you provided, especially when most cats aren't lucky enough to find a lifetime home.  And to have someone who cares enough to guide them to the end peacefully and painlessly, that is truly a gift.