The FPR housing is extremely weak, I turned it like 1/4 way to tighten and it snapped right off, so think about that before moving forward (read my posts on broken fpr housing, either here or on ford-trucks). I used the middle spring and I did notice it being a little peppier.
I did about 90% of the bowl rebuild, I did not remove the heater. Also if you remove the bowl from the truck (recommended) replace the compression fittings on the fuel lines (4). The old ones are a pain in the rear to remove, I used a pick kit from Harbor Freight (about $1.99). Also, watch where you rest your body. While I was laying on the engine trying to remove the old fittings the Alternator was a perfect resting place for my right elbow, well wouldn't you know it that I snapped the frigging positive charging cable lug right off! That actually was a blessing in disguise because it was about to break off anyway from corrosion and age. I also used Gasoila on all the fuel line threads.
The directions on Guzzle's site are awesome (so is he by the way, very responsive to questions), but I also did a YouTube search on this and found some good videos on fuel bowl rebuilds.
Hope this helps a little