If I've followed your other posts correctly, you got this car for cheap because #1 piston was damaged. With this in mind, I'd suggest:
- Using the most direct path, get the bottom end back together and the car running again.
- Next, chase down the inevitable vacuum leaks and other common problems with a 30 year old car. Making a smoke tester would be a good project.
- When you're happy with how it's running, look into adding a MBC and a Wideband O2 gauge. Feel free to crank on the boost as much as you want, while watching the AFRs, and expect that you'll be looking for a new engine eventually (or maybe just head gasket if you're lucky).
- A non-leaking turbo and a 90+ manifold are a good upgrade that you can add later.
- As a start for porting, I think there are still old stealthfti pics/posts around -- try a google search for: "stealthfti 530 porting site:turbobricks.com"
If you've never taken a head apart before, try to find a junk head to practice on -- the kjet 398s are almost the same as the newer 530s, and are often scrap. Ask at a local old Volvo shop or post in wanted.
Get a giant c-clamp and a plumbing pipe cap to make your own valve spring depressor. Take the junk head apart while paying attention to the precise fit of lifters into head. Imagine the cam destruction (flattening) that can occur if a bit of porting debris would get stuck in the lifter bore. After disassembly, try porting the head. It's junk already. Try lapping the valves too.
After you've practiced, and have decided if or how much porting you want, either find a good head or pull the head from the car.