Knocking 340

i'put down a sheet of 3/4 "plywood on the floor with a few 4x4 to keep it stable with some old tires as well , some these new trucks have plastic floors like my buddies pathfinder , had to use plywood on the floor with some 4x4 blocks and tires to keep the engine from moving to much . got my 440 home no problem
Good luck with your 340 i'd most probably buy for that price as well .