Diesel/LPG Convert

I have had Nissan Patrol Cab Chassis 4.2 Turbo I/C done recently and more than happy. As far as extra km and worth, I think (I'm no expert) 20-25% diesel use is replaced by gas, i.e., if you use 80l diesel + 20l gas the saving is paying gas price instead of diesel (about $20 in this example). I'm sure power to weight and other things may impact, but I have a feeling there is a finite amount of bang for the amount of fuel, or there abouts. Perhaps someone with scientific bent on the forum may shed some light.
As for power 20%+, torque 20%+, quiter, smoother and cleaner motor, I cannot offer qualified figures, but believe them to be true and accurate.

I'm glad I did it.

I have a question for anyone on the forum:
Seeing as the gas is injected before turbo and is cold (apparently fuel/air at cylinder is 100c colder than straight diesel) would the intercooler be actually more likely to raise the air temp, and its restrictive nature outweigh its benefit.