Cam suggestions

I'm actually on just about the same path as you. I will soon be installing GT40p's with an Explorer intake and a cam on my '87. For a while I've been trying to figure out what cam to install and I'm thinking that the TFS stage 1 looks the best for my needs without spending top dollar. My machinist is a big Ford guy and has at least one built Fox Mustang and he seems to have lot's of small block Ford knowledge. I asked him about cams for my set up and his first suggestion was the Trick Flow stage 1. He was also insistent on me replacing the valve springs in the P heads and thinks the TFS spring kit is the way to go. I think the only difference between your setup and mine is that you will be running 1.7 rockers and I will be using 1.6's. It seems like I've heard of people running 1.7's with P heads and the stage 1 cam but you should definitely research that thoroughly. I hope to to install my H/C/I by the beginning of May so I will let you know how everything works out.
Here are the specs on the cam: http://WWW.trickflow.com/partdetail.asp?part=TFS-51402000&autoview=sku

You are going to need the springs with 1.7 rockers.

When I bought my heads they came with crane roller rockers which I was told were 1.6's. Last night I googled the part # of the rockers and found that they are in fact 1.7's from the 5.0 cobra's. After doing a little research it sounds like running 1.7's with the trick flow cam could be dicey. I think I'm going to use my stock rockers or get some 1.6 rollers just to be on the safe side. I think the tfs cam's powerband starts at 2000 according to the specs on the website.

The tfs stage 1 is pretty mild.
While i always suggest checking clearances, i doubt with that cam and 1.7's you will have any issues.

IMO, you need springs no matter what, yes you are less likely to float valves with 1.6's, it's still a possibility when adding any cam to any stock heads.

I'd put on better springs and just run the 1.7's.