What I know: TH350: clutches and 4" shorter than a TH400. NP 203 & 205 models TH400: strongest GM auto tranny of its era. NP 203, 205, 208 models 700R: Lowest 1st gear, post-'89 are more desireable, OD, TV cable what am I missing? also what makes the TH400 stonger than the TH350? TIA!