Diff questions

[lincpimp]

Ok, so most here have seen my 8s 14xl powered savage. Completely stock so far. All I have upgraded is the center driveshafts, went to the heavy duty hpi cvds.

Now I just blew out the front diff, a 2 spider unit. I have a 4 spider in the rear, with a stock plastic case. Should I buy the flm 7075 diff cups, or the complete hybrid bulks? I like plastic stuff, as it is cheap to replace!

Any ideas or info is handy, as I do not have much experiece with the savage. I really like the truck, and it seems very sturdy so far.

Also , any info on diff shimming? I am sure that if I go with the hybrid bulks, shimming will be necessary. What about with the stock bulks/cases and the flm diff cups? Any links to shims will also be appreciated!