you can always use 2 lengths with a connector in the middle. some preflared lines are readily available at the parts stores in different lengths. they should have a union as well. a good tube bender is an asset. some lines will bend easier than others, different alloys, but that also means they will kink easier too. grab some vacuum plugs to cap the ends of the lines so you don't get junk in the lines as you run then in and out of the frame as you bend them up to fit. the frames are fairly straight compared to newer vehicles so once you get past the trans cross member and the area behind the cab it should be easier going. if getting a bender get one for your size of tubing, not a universal fit one, they tend to kink the lines. I have a couple different ones but always come back to one like this
https://www.aircraftspruce.ca/catalo...gaAvk7EALw_wcB
a pair of these pliers is also handy for a tight bend into, say, a wheel cylinder
https://www.harborfreight.com/tube-b...ers-95782.html
I find this style tends to kink because they don't fit the diameter of the line well
https://www.amazon.com/WennoW-Bender.../dp/B06XPTLPWD