if I understand it correctly it will allow me to repair any pistol with any pistol and rifle with any rifle any head gear with any other type of head gear ? or do i have this wrong ?

Yes it's well worth taking as you can repair high level stuff with low level stuff. This way you shouldn't have to worry about constant repairs. The only real issues with this perk are the fact you need 90 (or more) repair skill, and you also need to be careful as you may accidentally use a Unique weapon to repair a low level weapon. The same applies for Apprel too.

However, the way the perk works is as follows.

• One handed guns (Such as Pistols, 9MM and 10MM smg's) can be repaired by any non energy one handed guns.
  
• Two handed guns (such as rifles and shotguns) can reapir other two handed guns.
  
• Medium Apprel repairs medium apperel.

You get the idea.

You can also use this perk to make substantial profit.


If you're looking for a better description then check out the following link, it will tell you everything about this perk. (Fallout Wiki)

http://fallout.wikia.com/wiki/Jury_Rigging

o_0 is this a glitch ? I repaired a proton axe with a throwing proton axe to full dura

also needing 90 repair doesn't bother me just got that level with my last level up and took this perk few minutes ago + im running out of things to spend skill points on and only level 30 .-. by level 50 will all stats be level 100 ?

No no glitch, since the game classes them as the same weapon you are able to do that. No, it's impossible to have alll stats at 100 by level 50. You can have them all high but not 100.

what if skill book crafting ?