I'm nearing completion on my Countach build and seen the front drivers side was starting to settle (more than the passinger side). I bought a set of Moog springs with a spring rate of 450lbs. Now I know the stock rate is around 205, I'v mounted the battery up front however the spare will ride in the trunk, so the weight difference will be small. What kind of ride should I expect from these springs? Keep in mind I want the front low and will have to cut the Moogs to acheive a proper ride height (I'm looking for about a 2" clearance between the tire and wheel well).
I see there hasn't been a lot of feedback yet so I'll take a stab at it. I don't have any experience with a front spring rate in a Fiero that high, though my first thought when I read your post was that it seemed way too high for a street car. That kind of spring rate won't allow the suspension to do it's job very well since it will only allow less than half as much travel for the same bump or roll compared to a stock car. It could also prove to be tough on mounts for everything like the hinges of your headlight pods, to the dash, and more importantly the fiberglass panels mounted to the front (likely highly modified) chassis. If you don't let the springs absorb the road shocks they'll be transferred to the chassis instead, and depending on the extent of the modifications, you could see a fair bit of flex. Over time, that flex could develop into stress cracks in the fiberglass too. Cutting them will make it worse since as already mentioned it will make them even stiffer.
If you Google "spring rate calculator" there are several on line programs that can help you determine a ball park spring rate given a few measurements. In your case where you're worried about bottoming out with your lowered body work, I'd take the results with a grain of salt. I think for my project, one program recommended a spring rate of 200 lb/in and I opted for 300 lb/in instead. If I were you, I'd consider something along that magnitude too.
Here's a good thread with some information on 88 front springs. It looks like Steven Snyder is running much stiffer springs on a track car, but you may have trouble finding a damper that can match the high spring rates.