Welcome to the forum and the service. Hooyah, Oorah, Hooah, or whatever the Chair Force says, as it applies. Just ribbing you about the Chair Force.
That being said, here goes...
First: Get everything on your new girl good to go. If she leaks, plug it. If she smokes, track it down. If she's dirty, deep clean her. Make her perform and look like she just rolled off the showroom floor. This will give you an excellent blank canvas.
Second: Figure out what this car is for. Is she a drifter? A dragster? A show car? A spirited daily driver? Are you planning on entering competitions? Do you want to get much tail and many tickets? Do you just want to have fun getting from home to work as quickly as possible?
Third: Name your new girl. With a girls name. Something that fits her personality and yours. It's a little psychological trick the military has been using for generations. If you name something, you form a bond with it (her), and will pay extra close attention.
Fourth: Once you've completed steps 1-3, start browsing this site (and others) for parts lists, parts reviews and writeups for whatever you plan to do. USE THE SEARCH BUTTON! USE THE SEARCH BUTTON! USE THE SEARCH BUTTON! This forum is a veritable cornucopia of information. Don't be afraid to ask any questions, but search first.
Fifth: Once you've compiled a complete list of EVERYTHING you need to turn your girl into whatever you want the final project to be, prioritize that list by what you want to complete first, by system. Example: Suspension, engine rebuild, engine turbo, body kit, paint, new sound system.....
Sixth: Do not go cheap on these parts. Save your money (DO NOT GO INTO DEBT TO FUND THIS PROJECT ie credit card) and slowly gather quality parts. Ebay is cheaper for a reason. Occasionally you luck out and get an incredible deal on quality parts, but usually its like playing russian roulette with a shotgun. I'm taking a wild shot in the dark and saying you're between E-1 and E-3. I know exactly how much (or rather, how little) we make, so go easy. As long as your girl is reliable, everything else can take its time. Deployments are a great way to save money. Set aside a certain, affordable amount of your paycheck as your "repair fund". Once you have about $1000 set aside, LEAVE IT ALONE, and start another piggy bank with the same concept, call it a "modification fund".
If it sounds like I'm lecturing, I'm trying not too. I've had too many of my junior guys get into a hole because they blew all their money on a turbo kit, left no money for gas or food, and then blew up their motor, leaving them with absolutely nothing. I've been doing this for 10 years now, and have done the same thing back in the day. All this is my standard "Just got out of boot" training. Take notes and pass it on when you get guys under you.
All that being said, I would recommend your first modification (after all cleaning and repairs are done) would be suspension. The KA is a capable motor, and a decent suspension setup is the easiest and cheapest way to get that power to the ground. Some chassis stiffening bars will help too.
If you plan to turbo, the safest way is to pick up a KA somewhere, completely rebuild it, and turbo it while its on the engine stand.
If you have MWR hobby shop facilities available, I highly recommend using them. Get in good with the people who run the shop, and the advice and tools will come flowing. I bribe the manager with a case of redbull when I go in, gets me a couple free hours of lift time.
Ok, that's all I have for now. Feel free to pester me with questions, or tell me to butt out.
Good luck, and take lots of pics!
We love pics.
)
Been waiting 8 years for a 240, found one with a straight body and low milage. 
