what are the best gears ratios for a freeway flyer tans

I have a 091 transmoission and a another from a 1975 bus both standard. The 091 is jumpimg a gear(4th) and the 1975 needs a reverse gear. I have them both down and appart forrebuilt and i want to know what are the best and recomended gear ratio for the 091-1979 bus tranny , and if there is some kind of modification on the bus 75. I found the 75 to be the first that i see with so many different parts. never worked on any like this one( the 75 standard bus tranny). The gears instead of having lots of shyncro dents as the 091 , and even all the gears , are only made with 4 "dents"( i call them like this because i don't know how to call them). Instaed of having all this "dents" i only see that it goes with 4 heavy and big "teeth".Lets say that is not looking like the "start" type, just 4,each in 4 equal points and centered. Any ideas. I want it to accelerate fast on 1rts and 2nd, and go easy on RPM's at 3rd and 4th.Thanks.