EFi could be a number of outlets.... 034 motorsports in the states do kits, Emerald is a major UK supplier and the benefit of dave walker being a tuning mapping god also helps but its pricey... I know alot of people running cars on emerald though and they can vouch its worth the money...
http://www.emeraldm3d.com/
Tubular manifold hasnt been done afaik... Its a case of getting a design done that fits in the space... I have considered this on my car but again its not really been tested on CQs so alot of design work will be needed. Befriend someone with mandrel bender and a few free hours...