Reading my post, I notice I never detailed what I did:
1. Removed the MaxxAir Fan and placed small tarp over opening.
2. Removed wheels with tires
and replaced with 16" Ø steel wheels.
3. Pulled the Trillium
into the garage using a 'come-along'. About $22 at my neighborhood hardware store.
Lacking a place to anchor the come-along, I placed three 4×4's in a pi shape. That is, I laid two perpendicular to the garage door opening butting them up against the cement part of the walls, then laying the third one across the top and looped the come along cable around that. I found that once I got onto the smooth cement of the garage floor, the trailer rolled easily.
4. I pulled it in tongue first because I could place mowers etc on either side of the tongue and didn't have to have the garage cleared for the full width of the trailer to full length. Actually, I had a small cabinet I didn't want to move and the tongue fit in front of that.
5. I picked the first of the month to go to the garage and plug in the electric power for one day to keep the battery
6. I did put in pink antifreeze because I figured it was cheap insurance.
Because of the construction of the garage, I couldn't raise the door opening. Never thought of that when I bought the house. Actually, a 20' sailboat fit in the same place, but it was not as tall, nor as bulky. If I need only one inch, I could remove the trim above the door. Beyond that, I am hitting the gutter and any modification gets nasty fast.