These bar clamps could be used to hold a threaded assembly with a shaft seized inside it, their length provides valuable additional leverage.

WORKPRO 305 mm Ratchet Bar Clamp Set, 440 mm Spreader, Quick Release and One-Handed Clamp, Ideal for Woodworking and DIY Projects, Max 68 kg Load Limit, 2 Pack
5.0

SHALL 4-Pack Bar Clamps Set, Clamps for Woodwork Heavy Duty,12" (304mm) Reach, 660 lbs (272 kg) Clamping Force, Stainless Steel Woodworking Clamps
4.0