Hate to be the bearer of bad news, but the holes in the base aren't threaded, they are simply clearance holes for bolts to hold the machine to the floor, and for most purposes gravity works well enough.
To raise the machine get yourself a 4 or 5 foot long pry bar, and bring a whole bunch of 1/2" or 2/4" plywood squares, about 6" x 6", for blocking. You'll find the machine has a small slot in the bottom center of the front of the base that is just big enough for the tip if the bar. lift here, block the front corners, then lift the back corners and block. Keep going round and round until the machine is high enough.
Unless the machine has to travel a long way, I don't like to use a pallet jack. The tricycle wheel arrangement of a pallet jack can be tippy under a Bridgeport, and if the jack starts to tip, the machine will slide off. I prefer to use three or four lengths of 3/4 or 1" water pipe long enough to span both edges of the hollow base. 1" pipe is better, but lots of people have Pony clamps made with 3/4, and that will work almost as well. The pipe rollers keep the machine low enough to the ground that it can't topple over if it slides off.
Either way, lower the knee as low as it will go before moving to lower the center of gravity.
Good luck with the move.