The tune shouldn't change as I re-used many of the components from my rear mount turbo setup. I bought myself a Miller TIG welder so I built a log manifold to learn how to weld.
The wastegate is the silver valve down low behind the oil pan that is shown in the video. Sorry about the quality, I tried to chop out the dark section but the edit didn't work on YouTube.
Rear mounts always rely on an electric oil pump to return the turbo oil back to the engine. These can be unreliable and don't always get the job done. Mounting the turbo up front is also much more efficient plus safer for driving in wet conditions or off-roading.
The truck is completely built from the ground up. The only thing left on the list is a much larger turbo for track use. My current one is good on the street, not so much on the track.
Three summers ago I ran a 12.300 before any of the junk I have on it now. My local track is now permanently closed, so I don't know when my next track visit will be.