We used to use the old squirt bottle full of gas and would shoot it into the tubes from the opening of the hood scoop. Did not always work well.. When the motor was cold it was an outright pain in the butt.
Then we changed the system around. In the Scoop pan we bent up a piece of steel line that is conected to a solenoid. When we start the car now, we turn the fuel shut off, on.. press the primer button 2x and then the starter button and the primer button on/off quickly. the motor starts great, and we continue to hit the primer until the motor gets enough alcohol to run on its own. With the motor getting 8 shots of fuel out 1 time the motor fires up like it has a MSD. We use a Vertex mag on the car.
When I put the Tunnel Ram Injection on my car I drilled the plenum and installed a tube with holes drilled in it to shoot fuel down each port on a primer circuit. it is a vertical infecor and I really like it because I can start the car everytime without having to take the hood off.