So I'm getting all my parts together to put my 73 dart back together and a different rear end is the last on my list. Currently it has the wimpy 71/4 in it, and I'm putting a 360 in that has close to 400hp or more, so I don't think it will take that power very well lol. Are all A body rear ends the same? (Width wise ect) and will it bolt up without modification? Or will I need to change something? My grandpa has an old 68 barracuda for a parts car that has a 83/4 3.55 (not 100% sure about gears) would I be able to take it out and directly bolt it into my dart? New leafs and some other parts will be replaced though. And could I use my driveshaft with that rear end? Or is the length slightly different?