as far as efi goes i was thinking of putting that into my panelvan as i am restoring it at the minute, it would be a nice power increase good economy with the 4 speed the let downs are the $700 worth of wiring i have been quoted to match it into my van, the look i dont like the look of efi in an older car, if anything goes wrong i dont know how to fix it every things electric and foreign to me, if i was you, if you use the car everyday and just want better economy, i would buy a ute with a gas system on it (not a really old system) you should be able to get a ute for about $1000 transfer it onto your ute leaving the ends for a mechanic to hook up as he has to certify it and will want to ensure no leaks/ couplings are good etc you may need the tank stamped so if you allow $1000 for a ute $1000 for the mechanic you should be right and you have a ute sitting there to on sell or part out the spare ute will still be drivable on petrol may just need a tune,
if thats all too hard come see me ill pull a complete system off sit it in the back of your ute for $200-$300 (depending on what the bloke i wreck the cars with wants) we both own half of everything, go get the tank stamped and pay a mechanic, either way your still up for $1500- $2000 for a second hand system or pay $2000- $3000 for a new one