12 - 14 actually seems a little low for stock. Both my 12v's ran around 20psi stock, now granted one had the wh1c so it would run a little different than an hx35. Check yours to make sure it dont have a boost leak. It may be fine but worth a check.
First off start with guages before anything. They are a fairly inexpensive insurance compared to a blown motor or tranny. Now you didnt say if its auto or manual (or I missed it) so be prepared for either an auto build or a good clutch even with a small power increase.
For exhaust check with farmboy. Gus has about the best price you can find and you can order 4" or 5", muffler or no. Fitment is great just installed his setup last week on an 07 CR.
Shave the fuel plate to a #0 and leave a very small ramp at the bottom. Slide the plate about 3/4 of the way forward, not all the way. Ive done probably 20 of these in the past and putting it full forward usually actually chokes the motor out more than it helps on a fairly stock truck. Go ahead and spend the money on a boost elbow and turn the afc. Go to napa and get a BHAF, it fits in the stock intake elbow, I liked mine it worked great. Cant remember the part # but search cumminsforum its easy to find.
Now after that if you want a little more power check out some of farmboys injectors or delivery valves but you better be ready for a turbo and studs. Oh yea I forgot to mention keep a listen out for the stock clamps to let go on the intercooler boots. They dont like 40psi of boost.
Welcome to the world of diesels, now you can never go back. Feel free to pm me with any questions, I have many years and many hours under the hoods of 12v and 24v's.
