If it is an original, in great condition, it is worth $1,000,000!!!
There is no horn relay on a 1970 mustang
Yes a 429 would fit into a 1969-1970 ford mustang without no engine compartment mods
NO! the mustang II has a softer front suspension that is only designed to hold a puny 4 cylinder and a 70' has a v8 unless its the I6.
Almost any muscle car CAN pop a wheelie. It just depends how thick your wallet is. You have to pump the torque like mad in it.