Fred is wrapped up in a bunch of red tape!

Yes, he's wrapped up very tightly.  In fact, he looks a lot like a mummy

There is another mummy in this time that might help serve as a decoy.

You need to get Cousin Ted from in front of the motel up to this room.

You're going to have to find some form of leverage to bring Ted up.

Have you looked at everything near this room?  Something will serve as
that piece of leverage.

The pulley on the roof will let you bring Ted up to this room.

To work a pulley, you need rope.

Dr. Fred is being tied up with some, so take it.

Then tie the rope to the pulley, run down, and attach it to Ted.

Go back up to the roof and pull on the rope to bring Ted near Fred.

Before you can switch Fred and Ted, you need to make the two look identical.
You can't fool the IRS too easily, after all.

The only difference between the two is their color.

Just paint Ted with the red paint from the attic in Hoagie's time.