The front and rear torque boxes were used in different applications...Small and big block...I could tell you "the torque boxes were used in XXX applications" but there seems to be many exceptions on their use with or without them...The rears seem to be much more common than the fronts..I'm not aware of any factory core support bracing from the factory but the aftermarket seems to see a need for it..And lastly don't forget about considering the K frame skidplate if you're using the factory 6qt oil pan..

It really comes down to what you intend to do with the car..Even a "mild" 440 by today's standards is still more HP than the factory offered back then..If you're just cruising around you probably don't need any more than you have..But if you like occasional road blasts then adding some performance/safety enhancements is a good thing...