I used the A-frame design mentioned by Marunio on my First 26 (about 30' mast). Worked great except for a small mishap when we stopped paying attention to the mast while messing around with one of the stays.
The mast started toppling over, but the winch rope caught it. We were able to hoist it back and maneuver it down without further mishap.
As you can see - just four 12' 2x4's, some line (tied at back and front cleats, and the line through the block at the top.
One thing, make sure the line is hoisted above the mid point of the mast when you untie the stays.
When I putting the mast back up though, I will first try to not use the A-frame
My mast step has a set-up that I can use as a hinge (see pic - you can see why the mast had to come down....rotten running rigging and sheaves) - I'll drill through the base, insert a hinge and then "hook" the mast step to this.
I'll prevent the mast from swaying to sides by tethering the stays with line to the chainplates or more likely through my genoa lead cars.
Pivoting the mast at the base, keeping it straight with the lines through the lead cars while lifting from the back and hoisting by the jib stay might work - I hope
If not, I'm pretty sure the A-frame will do it.