I have bought a few things for my cummins. Its an 03.
What kind of truck is it?
I prefer to use a local diesel shop such as turbo injectors etc etc etc and a randys stage 3 tranny. I like to have a warranty with someone. Anything that's going to beef it up a warranty is a must. Back in october i blew my input shaft on my stage 3 tranny. Thats a 1000hp rated tranny and my 550hp truck found a way to break it
But if your looking for small items like a fass fuel system to head studs or cold air intake then yes.
I will be honest dont know much about the 6.7 powerstroke. Only a handful people i know that boost them up use SCT. I always use to read diesel power magazine and see the builds they do from small to big
Last couple years the magazine went downhill and paper thin with less info.
Buy an old one...the guy that rebuilt my corona pick-up did a fantastic job..7.3 international and it has plenty of poop..even towing a horse trailer with 4 big ass horses in it..Bess would be proud...70-75 mph no problem and 14 miles to the gallon..love the 2 tanks..got a 550 mile range..nice here in Wyoming..