I may have an answer from
http://bg.battletech.com/forums/index.php/topic,33178.0.html and I'll collect and summarize (and post to the other thread I made, I believe these can both be considerd 'answered' unless the staff would like to research more which I welcome)
Injury mods can stack up into the -4/-5 but medical gear can reduce that to a 1pt penalty... and that lines up the TNs.
The Technician - skills in StratOps are all based on the same TW roll-under system, so have to be considered as inverse.
In essence, you start with a TN of 8, subtract the average of the skills needed for the job and compare that to the TN in the table you're referring to. This gives the equivalent experience level for that task, and the TN they'd need.
My personal solution is going to be straight using AToW skills and check values when they are available and the Support Personnel StratOps approximations when they are not.