Utility Cycling - How can I get a fork mount to pivot?

I am trying to make a tow assembly to tow a bicycle on my rear rack. I ran onto 1 problem, the fork mount I am using doesn't allow pivoting. Can anyone think of a way to modify it to allow the fork to pivot?
Here's a thread in the carfree forum with pictures:
http://www.bikeforums.net/showpost.php?p=7435256&postcount=8

A lazy susan bearing (http://woodworker.com/cgi-bin/FULLPRES.exe?PARTNUM=895-544&search=Lazy%20Susan) between the wood block and the rack. I've occasionally seen them at hardware stores, even the big box ones, but the best selection at Woodworker's Supply (link above).

take an old front hub w/ quickrelease. Use Ubolts to attach it to your chunk of wood.

The problem with towing a bike up that high, it become unwieldy. the best towing happens when the bike is level. use BOB trailer with the extra hub and wood set up. you might even be able to Ubolt the hub directly to the floor of the BOb

A lazy susan bearing (http://woodworker.com/cgi-bin/FULLPRES.exe?PARTNUM=895-544&search=Lazy%20Susan) between the wood block and the rack. I've occasionally seen them at hardware stores, even the big box ones, but the best selection at Woodworker's Supply (link above).

No need, the bike under tow will pivot around its headtube.

Cman has the answer.

Nice idea with the hub, I thought about that, but it doesn't mount as clean as a 'screw down' fork mount on a piece of wood. I really don't have a problem towing it with the fork sitting up high...it is not that much weight. As far as the lazy susan goes, well, I wasn't speaking about the lateral movement, I need it to pivot up and down, the headset will take care of side by side motion. Anyone know of any really thin bearings I could put on the fork mount to allow movement.

Maybe a piano hinge?

Two different possible solutions:

1 Put a small fork on the tow bike, like a 16" or 12,5" or cut the present down alot. OR

2 Bend the front axel out a bit to fit on the rear wheel. Attach it to the rear wheel axel or put some extra bolts on your bike just abowe the rear axel. There is often a triangular hole just abowe the rear dropouts.

Rather than letting the fork pivot about the mount, why don't you make the mount pivot about the wood block? I'm think that you could screw a door hinge down to the wood block and then bolt the mount to the other side of the hinge.