I don't mean to sound flippant or indecisive but I got off track in my objections. I might actually want to raise the roof high enough to add three layers of block. I might want to add another panel to the garage door for extra clearance for possibly a truck with racks.
I appreciate the previous advice and I'm sure many in the community may have benefitted from the responses. I'd like to now figure how to raise the roof the best way and if anyone would prefer framing instead of blocking to fill. Also, I'm guessing temporary blocks stacked up would be the most stable temporary support. With the windy season coming, I would Want to take less chances; or maybe lay one course at a time. Maybe for this reason, the block would be better than framing.
It seems, for starters, knocking blocks out for running beams through the corners under the sill plates would be a good start; then jack just the corners with four bottle jacks, while blocking up inside for support.
I won't like buying all that block for temporary support but can't think of another way.