Info wanted on engine things...

no disrespect intended to anyone - 73 318 rods will likely not be bushed and be the same as a 360 rod, at least those Ive taken apart are built this way, bushed rods in 318's were supposed to have stopped in 72. These 73 rods will be heavier than those used in a 273 as well (beefier = heavier parts). If you want to use these rods with the 273 crank the crank and or rods will need to be balanced. If you get it apart post the forging number from the rods, thats one sure way to know what they are.

Hope this helps !