Just finished installing my Rough country 4in lift(with pics)... Have a few questions

I have finished installing the rc 4in lift and i have to say i am pleased with how it turned out. It wheels nice too!

more recent pictures from last wheeling trip some are my buddies jeeps:














Before lift:


After:







Its much higher and looks great. Although it was anything but easy going. Since ive wheeled it and the jeep is an 01 there was a ton of rusty bolts, a few of which i broke. This brings me to a few questions:

1)I broke one bolt on the rear right upper shock mount and half the bolt is in the body nut still. Any suggestions other then drill it a get a tap? What size tap?

2)With all my horrible luck my torque wrench never clicked when tightening the last lower control arm bolt (arm to body) on the driver rear and i ended up twisting it in half and welding part of it to the frame which made the hole 1.5mm smaller and i had to re-drill the hole. Since jeep wanted $35 for new lower control arm bolt and nut and could not get it until wednesday or thursday i went to O'reilly's and picked up a grade 5 metric bolt (although it says 8.8 on the head of the bolt) for $2 with the exact same OD as the stock bolt (13.75mm). My question is should this just be a temporary fix or would the grade 5 (or 8.8?) metric bolt be strong enough to withstand off road use?

3) Again with my rusty bolt twisting luck i broke the drag link bolt that attaches to the axle as i was removing it. I ended up using one of the bolts from the rough country lift. It says 8.8 on the head of the bolt. My question is will this bolt be strong enough?

Other then the above problems install wasn't half bad just very time consuming as the amount of work is deceiving. After 14 hours of non stop work, some cursing, a few "cold refreshments", and no sleep for a night we finally got everything installed and it finally looks like an off road beast.

Thanks in advance for any input.