I would be more than willing to help with it if I was home. I have never done it or personally known anyone, but it looks easy enough. The only thing I would consider is you have to be careful about creating too much backpressure on the exhaust because if it's excessive it can hold the exhaust valve open and cause problems. I know lots of people have them though and I don't hear too many complaints so....
In fact....Straight from Jacobs Vehicle Systems website.
Jacobs Vehicle Systems - Frequently Asked Questions
Do you make a product for the Ford 7.3L Powerstroke or Navistar International T444E engines?
No, Jacobs does not offer an exhaust or engine brake for these engines in fact, Navistar and Ford have requested that we do not develop one for these engines.
The primary concern with putting a retarder on these engines is their use of hydraulic lifters. Most engines with hydraulic lifters have fairly low exhaust back pressure limits so the performance of an exhaust brake would not be substantial. More importantly the use of an exhaust brake on an engine with hydraulic lifters can cause engine damage. The problem is that the increased back pressure resulting from the operation of the exhaust brake will cause some degree of valve float. This valve float can cause the hydraulic lifter to re-set with the valve still open (not seated). This phenomenon is known as lifter jacking. Lifter jacking could also result if a traditional engine brake were used on these engines. The results of lifter jacking can be anything from low positive power (because the valves stay open) to engine damage caused by valve to piston contact.
I hardly ever see anyone mention this and other similar problems with exhaust brakes on our trucks so I don't know what the deal is. Maybe it is a non issue and I am not necessarily trying to steer you away from it, just making sure you have all the info.