I am looking for information on where to park the car that transports the bikes to the greenway- -above the GWB I think would be my best bet since coming from PA across the bridge and there is an access point around 181 ST---yes/no--thank you...
When do you plan to ride. Day-of-the-week is important.
On Saturday or Sunday you should be able to find street parking. Take a careful look at the neighborhood before you leave your car, and remember how to get back to it.
Or find a lot with a good all-day rate. I can't help you that far uptown.
You might find parking in Fort Lee and ride across the GW Bridge. I'd let you park at my old place, but I moved from there years ago and they tore it down since.
Or you could stay with your son and take the subway over.
I've noticed people loading and unloading bikes on Dykeman, just west of what must be Staff Street, near the river and Dykeman ballfields. It might not be quite as convenient as the neighborhood surrounding the George Washington Bridge but it's relatively easy to access the Greenway from there. From there you can just go up Staff Street, turn right to go under the underpass, and take the staircase on the right. It will leave you at the northern most tip of what's currently the Manhattan Waterfront Greenway. The GWB is about a mile south.
Come to think of it, when I was on the Greenway last month, I saw people unloading bikes at a parking lot on the Greenway near 130th street. It's the place where the Greenway detours for a couple of blocks before returning to the river. I didn't check the signs at the lot entrance, so I don't know if there are any restrictions. At 4:00 on a sunday afternoon it was mostly empty.