What we use here on the Goiter & Pacific is those pump-up weed sprayers. They are as cheap as hell and they work really good! Talk about a reach, you can spray oil on the opposite driving box just by reaching across the frame! And they can be made to look authentic by painting them with some metalic grey Krylon. The better ones come with a shoulder strap which works well. (3 gallons of oil weighs a lot.) We can go at least four days on one fill-up. And when one breaks, we just go to the feed and seed for another one! Problem solved.