Implant/Bio- Surgeon

So, I have been playing the game for a bit now and I have spent the points several times to het the aforementioned infamy perks. Where do I spend credits on mind wipes? And what is it? And where is the implant surgeon, and what are they selling that the perk give me a discount for. Also is the highest weapon tier 5? many other questions...but lets work on this. Also my questions may have been answered before and I just couldn't find them on the forums.

Mind Wipe is the "wipe" to remove a skill. Cost goes up per character per use.

Bionics go to injury screen after you lose a limb. You can buy a cool replacement with stat bonuses. If I recall I lost a leg, which has a terrible modifier, but my bionic gave me a +MP boost after I got it.

There are occasionally Tier VI weapons. I've found them every so often on higher difficulty operations. I think brutal and deadly? Never seen them in the shop, personally.

There's rank 6 armor based a trophy description but yet to see any. The difficulty has a number just above the name which I believe corresponds roughly to the level of gear, sometimes higher levels will be found. I played brutal and stole every weapon I could and got 3 level 6 weapons total. I've tried deadly with top level chars and gear and got my ass handed to me in 2nd turn of the first match so I gave up lol (see other thread).

Maiming and death seem to have about the same probability, pretty low as I've only had 1 of each, but the bionics are pretty sweet bonuses once you buy them. A little confusing as you buy them on the injuries menu