the trans go junior helps the transmission hold more power even at the moderate levels before it becomes toast. pretty much once you even limp it once under power its more prone to do it again getting easier and easier every time. its just like a tune or trans relearn witch you will get to know and under stand with owning a duramax but it wont **** harder or make it faster just allows the trans to be more efficient at holding power.

as for the switch it sounds like your talking about a DSP5 switch. witch with efi live is put in and you have a controller **** that you can switch between 5 different tunes ranging from stock,tow tune, smoke tune, street tune, and race tune.

the smoke switch is nothing more then tricking the computer to dump more fuel to make smoke but you can get "stupid" with it pretty easy and wash out the cylinder walls of oil witch causes the ring to wear and can cause the ring to fail

 

the transgo jr wont help the 5-speed very much, you need a full transgo kit to get the full benefit, and you have to drop the trans to do it, if your dropping the trans to do the full kit you may as well go further and rebuild it and put a full kit with a converter and clutches etc.

the turbo vane control switch you are looking for is made by Fleece performance

edit: I forgot to mention that yes the stock intake can be used to make 500hp with no issues, but if you want an aftermarket intake there really is no problem with it, in fact S&B is the one I would recommend

 

I was hoping there was something else other than their turbo brake cuz its like $900

 

sorry, thats the only turbo vane controller that I know of...

EFI live is probably your best bet for that

 

Ya that was my conclusion also.