It is great to have a source of this information as I am making this modification.
Our mast does not have a foot welded to it. The mast step on deck has an elongated hole on each side in it for the bolt. As the mast goes forward, the loosened bolt slides up a bit in the mount. The forward bottom of the mast also has a rounded area to it.
My mast step has (will have) a slot (elongated hole) for the pin to slide up in while the base "rotates" through the arc created by the shape of the base. I will also radius the leading edge of the base of the mast. From looking at the base of Ed's mast in his video it looks like "cheeks" have been added to the outside of the mast to strengthen it where the hole for the pin is drilled. I understand that the only strain on the pin is during raising and lowering. Will it be overkill to add reinforcement at the sides of the base of the mast? I do plan to weld a piece of sch 40 aluminum with an id of the dia of the pin into the mast as reinforcement.
One thing that we have to watch out for is that once the mast is lowered, (or as you prep for raising) is that as it's base is ready for the bolt to go in, the top of the mast is far forward and tends to drop, so I have to hold the base down. Sit on it and then put the bolt through the sides of the mount and the mast base.
Do you know the distance from the step to the bow support on your boat?
I made a board that fits across our bow pulpit with a large trailer roller in it. Once the mast is down sitting on it' it's easy to just allow the base to rise up a bit (under control) and roll it back. I then support it on the bow pulpit (without the roller) forward, on the boom gallows aft and I use one of the wood 4x4s trailer chucks, that I special cut to to mount where the mast step is and it supports the middle of the mast for transport.
As chicken as I am, I had the mast raised for me the first time to make sure everything fits and is secure. Lowering is then easy and setting up the 4 part bridal is easy, and if not taken apart, the correct size for the raising.
If you need any close up photos, just ask and the next time I go to the boat I will snap a couple.
Thanks for all your help. Pictures of your step and the base of your mast would be great! A measurement of the length of your slot and the height of the pin's hole above the deck would be helpful. I think I have figured out dimensions that will work but confirmation is always good.