Try the trailer sailor forum or website.
I know it may not be a typical trailer boat but I'd post a thread in the trailer sailor forum or one on the TS website too. There's reams of info in the archives on stepping a mast with an A frame. We step my 26 mast, factory engineered for safety, all the time(on the water or on the trailer). Can't speak with any authority on a specific technique for your 25, except be very very careful especially if it doesn't have a hinged tabernacle. Short cuts and hastiness will bite you.Your wife is a generous gal "IF" she'll go up the mast especially if she's afraid of heights. You're on the right track in figuring out how to keep her safe and sound on deck and out of the rigging

Last resort but the safest....boat yard or hire a boom truck/crane. Maybe one of those Vegas tradesman/lighting/electrician guys with little boom truck who's looking for a quick job. Prep it ahead of time, 15min to set it on the deck and come back next day/week after your repairs.Be safe,Michael