No you cannot put it in the engine bay. It has to go in the back of the vehicle. This is not a mod for those who are not mechanically inclined. If you need it done the right way as a kit you can give me a buzz. I have extra parts to make like 3 systems for a turbo diesel. You would have to find your own regulator I think I only have one of them.
A surplus Acetylene Regulator with POL fitting is the perfect thing for this mod. You just need to replace the low side gauge with a 0 to 30 psi gauge.
I can do these in boost activated or digital progressive systems which inject based on how much boost your making using one of our controllers, Or you can find a pressure switch at a shop that is either adjustable or at least 5psi.
LPG will kick you in the butt every time it comes on. It's very effective.