Masthead access

[pressureangle]

I have a 25.5 Hunter sloop, with a 29' mast from deck. I lost the jib halyard to the masthead, and I need to install a windvane anyway, and check the anchor light to see about an LED setup.

My question is, is this rig heavy enough to allow me to go up? The only chair I've ridden was on an 86' Swan which was obviously a lot higher, but of unquestioned strength.
The mast is stepped at the deck with pins, so lowering it is a relatively easy option-can I lower it with the main halyard, and at what point will it over-center and need support from below? Is it a two-man job, and what risk is there at anchor as opposed to while hauled?

I'm a cheapskate, but I don't want to be in danger due to ignorance.

Eric