Hey there Gretsch,I will give you a Kiwis perspective on your search..I own a 1960 F100,imported from North Hills Ca about 5 years ago.Gave it a quick rebuild,fitted it out with a 302W and C4.Not a neck snapper by any stretch of the imagination,but,as it is my everyday business truck,long bed,a glass coupe body goes on real easy,which is why we bought it.It is what does the job.First thing to remember is these trucks have the aerodynamics of a brick..its gonna need a cunning combination of cubes and gear ratios to get the ideal economy,if thats what you want..I run mine on LPG,similar to your propane I guess,because it costs me about $1 a litre,against $1.75/litre for petrol.[3.8litres/US gal],4.5 litres/Imp.gal.One thing you could consider for your F100 if you buy one,is an injected small block,always gonna be better on gas.You guys have a better range of engines up there than we got.Its just a matter of finding the right truck.Good luck.