[This is my reply to a different post, but it applies here too.]
I personally would like a rail to fit the below injectors. This style is very common in the Mazda, Toyota, Honda, Acura and DSM crowd. The part#'s listed are Nippon Denso injectors that came on RX7's. I personally run the 460cc version. If you built rails for these type of injectors I'd bet you would sell enough to make it worth your while. The hard part is building a rail that seals the "O" rings properly. These injectors will easily fit in a L28 intake manifold by making a simple modification to the diameter of the pintle caps.
84-85 13B NT low square center 680cc orange 195500-0900
86-87 13B NT low square center 460cc red 195500-1350
86-87 13B T low square center 550cc tan 195500-1370
Thanks,