I went the Hilborn route on my McLaren M1B replica. This 2 7/16 stack system was a bit under USD $3k new from Hilborn five years ago. It comes with the original mechanical injection lines (not shown in this photo) plumbed into a distribution block in the valley for use with a MAP sensor. This, and the fact that the injectors are tucked into the inside makes it look a lot like a traditional mechanical set-up at first glance.