Go Jake !!!
If you were quoted $750 for your Jake installed, go for it! The Jake kit for my '05 (which includes the shifter stalk switch, BTW) was about $1,100 from my friendly Dodge dealer. It came in a Cummins box. Installation took me about 3-1/2 hours (jake brake, solenoid package, vacuum pump, new serpentine belt, stalk switch, wiring harness, relay and vacuum lines). It does wire into the 50-pin "B" connector on your ECM and a 32-pin connector on the driver's side firewall. NOTE: Be careful handling that coated shim steel gasket that goes between the turbo and the Jake, its VERY delicate and does not tolerate any kind of abrasion, impact or twisting during installation (I should know, I buggered one up and had to buy a replacement gasket from Cummins for a whopping $31. 00, Ouch !!!). To prevent this mistake from repeating itself, I dropped the headpipe on my 2nd install attempt, then "practiced" lining up the Jake with the turbo a few times with the damaged gasket until I got all the moves down right. Believe me, its real easy to destroy that gasket if the Jake slightly hits the turbo while you are aligning the dowel pins. Take your time with this step, and definitely think ahead with all of your moves when joining the Jake to the turbo! Other than that little setback, the rest of the installation is straight forward. The Jake works great and there are absolutely NO exhaust leaks. It sounds pretty cool with an aFe Stage-1 / Torque Tube combo too!