Fredico,
I have both 4 and 5 speed transmissions and Vacuum and Electric rears in my trucks. I always start in "low rear" normally in 2nd gear (unless I need "granny" for a steep hill start or and loaded). Then I just run the gears 2,3,4 or 2,3,4,5 then flip into "high rear" after the transmission is in high gear. It makes it seem like you're putting it into Over-drive...works for me!
Good luck and be safe!
Mike B
