I thought it would be good info to add this if you want to modify a 2001-2005 VVT fuel rail for use of EV14 injectors. I did this just because I had the tools and time and wanted to save a friend a bit of cash. I also wanted orings on the bottom, I'm just not a fan of boost and isolators.

2001-2005 fuel rail modifications
I used a mill to take the stock fuel hats down just past the nubs. (a dremel or grinder would probably do the job but wouldn't be pretty)
I used a 1/4 NPT tap to thread the fuel regulator port. I cut a second 1/4" NPT tap with a grinder to make a bottoming tap so I could tap deeper and get really good thread engagement.
I used a 1/4" NPT 90 degree barb fitting for the return.

Adapters:
Top side (fuel rail side) I used Honda adapters here : The Honda hat Orings were a little too tight but the stock VVT injector upper orings fir the adapters perfectly.

Bottom side (Head side) I used GM LS fuel injector hat adapters here : The upper ID and OD are perfect but I had to put them in a mini lathe and size the bottoms down. The head injector hole is stepped. After they were test fit I used Permetex Ultra Grey RTV to seal them into the head.
The LS hat adapter orings will fit the bottom of the EV14 injectors for a perfect seal.

The stock spacers and bolts fit after this. The fuel injectors required no modification.
Always remember to grease orings before fitting or installing.
You can use any type of vac referenced external fuel regulator this way. I really like the Aeromotive style regulators.
The injectors that I used in this project were Ford MU52 GT500 injectors.