Technical data sheet for 3M 4941 VHB Tape:
https://technicaldatasheets.3m.com/en_US?pif=000062
Shear strength is 70# per sq inch. Typical Z-bracket length 4", Width 1". 4sq" = 280# of shear strength per bracket x 4 brackets = 1,120 # of shear strength and 1,460# of tensile strength.