bucket seat question part 2

Hi gang... so.. in my ongoing saga to convert my Dart from bench to buckets.. heres where im at so far... I managed to score a nice set of A body seat tracks at the Nats.. they are 70 and up tracks.. I have heard (and the guy that sold them to me also said..) that the seat tracks for 67-69 are differant from 70 and up in that the later tracks have the seat up higher (the bottom of the seat was not as deep in the later seats.. how true that is I have no real clue... so.. piece one of the puzzle is found.. now.. another friend of mine has a set of buckets that he is willing to sell me very cheap (and with the money situation at the moment, thats key) only problem is they are B body buckets,.. out of a mid 70-s Charger or Magnum.. he was going to put them in his Scamp, but said they looked too big.. but when he got actual A body buckets he said they were a little narrower but not much.. In my case too wide doesnt bother me, as I am not going to run a console.. wide means more comfort to me,.. LOL .. my fear (or question) is, HOW differant are 70's A and B body buckets? Will the B body bucket be too deep (the seat part of the bucket)?? I dont want to get in and feel like I am sitting on phone books with my head smashed against the roof... any info or help here would be appreciated