Not much of a help from me, but have to say that I don't have a very good results by overwintering potted tulips neither in dark garage nor in exposed, but somewhat protected pots outside. they either sprouted very early and become spindly or were frozen to death.
The only limited success I had with potted tulips is when I half-buried pots in a soil or compost piles.
I call it 'limited success' due to the fact that I potted all leftovers, 2-3 of each of 5-7 varieties I was planting that season, in a same pot and since they all had a different bloom time, every pot was a mess and no impact, though they all bloomed nevertheless.

I never tried the garage method but tried the "in a pile of leaves" method and it was a failure. My suggestion is to bury the pots in the garden where there is space and then dig them up when the ground thaws. You are not going to get them to bloom much earlier than those in the ground but you will have some for the front steps etc. If the garage remains consistantly cool enough with out getting too cold it might work. You will have to make sure they dont dry out completely.