i have been talking to a wrecker about a spicer 6 speed trans. it has an overdrive. it came out of a mid- 70's dodge D3F ( forward control ) truck. this truck had a 6/354 perkins in it. so i'm hoping it has suitable steps between ratios. the guy was pretty vague about exactly which box it is. after looking on google, it might be a 1062 or 1272. has anyone had anything to do with this type of box ? were they any good ?