I had built a 500+ rwhp 98 cobra last year. I spent over 10K getting everything just right, although i did nothing for the engine. I was looking at another $10K to do the forged Long block -I would have gone with VT engines Big bore motor. It got to the point where I was afraid to dtive the car for fear of toasting the engine, leaving me stranded somewhere.
All in all, I just could not justify sinking anymore money into it. Plus, the 98 was used to begin with.
I decided to cut my losses, and start on a new platform and I have not looked back. The 03 already has the forged engine, it has the smooth shifting 6 speed, it handles like a dream compared to the 98, and its a vert (which I personally regretted not having in the 98).
Yes, I had to shovel out some $$$ for the cost of the vert, but I feel Im starting off on a much more solid platform.
For under 2K in mods, Im up around 450rwhp, and 470rwtq. The car is and feels way faster than the 98 because of the long torque curve.
Anyway, sorry so long!
peace