Johnny, I'm pretty sure a Dakota bench seat will be too wide for your truck. A Dakota bench seats 3 people across (close together) but I believe you only have room to seat 2 people. A pair of buckets out of a Dakota should work though, as long as they sit upright enough.
Also, I had a 39-47 Dodge pickup and if I had the seat low enough the seat back was under the back window ledge, that let the seat sit back another 2". I don't know if that would help on your older truck. Gene