The 65 f 100 has the i beam front axle what woulda better option ?maybe a frsme graft from a later model ttuck with ifs?
Like the others have said, a 65 truck should already have ifs in the form of twin I-beams. Nothing wrong with that design, simple and rugged, good camber curves for handling corners.
twin I is a good setup. I have a 03-08 crown vic in my 61, youll hear a lot of people that dont like it, but i love how my truck drives and if i need parts for it they are in stock about anywhere.
for a d/d leave it alone throw new king pins in it or grease the ones its got and call it a day disc brake spindles from 69 to 78 bolt on to lower it a little you can cut off 1 coil if you want more than 2 inches you need to use dream beams also ElPolocko sells a pretty cool dakota swap kit if you want rack and pinion steering monster brakes and have the front bumper less than 10 inches off the ground swap in a 2003-2010 crown vic/marquis/towncar front cradle its a bolt in swap. this is a great web site / forum for info and swap on 60's ford trucks http://fordification.com/
There is nothing wrong with twin I beam other than it is stupid, ugly, heavy, antiquated and does not maintain camber through its arc of travel. Add to the fact that it is hard to lower any more than a few inches due to the limitations of its basic design and the gianormous crossmember that comes with it. It is, however rugged and durable...but still stupid. For a farm truck, the I beam might be your best bet, but if you are looking to lower your truck to any degree, check out ElPolakos Dakota style front or maybe even a GM A arm clip. Mine has an 81 Olds Cutlass front clip and handles/rides perfectly and has full suspension travel. Good luck, -Abone.
If it has a single beam straight axle with leaf springs, you could have a 64 or earlier. It is real common to find these trucks misidentified by the DMV. Most of the time you find newer trucks titled or registered as older, for example a 66 tagged as a 65; it can go the other way like a 64 tagged as a 65. 65s will have the twin I beam emblem on the front fender instead of F-100 on the hood side. The 65-66s are great trucks that came standard with FE blocks and very good suspensions. Personally I like the pre-65 straight axle too. Rebuilt the ride is good. Its a real truck.