half shaft help

Okay, i found my borg warner 5 speed and r200 for my 71. From what i read I have to have half shafts from a r200 set-up ? They are different lengths on r200 vs. the same length on the r180? I also read that the driveshaft will need to be shortened because of the bw trans is longer. All these parts came off of a 1982zxt for reference. I also noticed that the bell housing on the bw trans had 2 support legs that bolted to the block on thezxt. Is this gonna be problem running without these?? Looking for professors in the school of hard knocks to teach me .

steve