if they are snapping bolts putting bolts on then probably bad bolts or somethings not straight.
if its breaking getting the old bolts off, then thats pretty typical.
they are typically titanium bolts and studs with locking nuts, which gall the threads very easily. to help avoid that use penetration oil. the day or two before hand if you can as it takes days for it to creep down the threads.
when you go to take the bolts off, once you get the first bit of movement, spray on some pentation oil and work it in (wriggle spanner back and forth).
btw you don't have to drown it in oil, just a little will do. you just need a tiny amount to get down that thread.
also have some replacements studs handy.