Welcome to Allpar. Sorry it took so long for me to dig out the book.
I have a Motor manual the lists the A-250 (non-synchro 1st gear) from 1962 to 1974. The fully synchronized A-230 was a relief from crunching 1st gears from 1974-on. The applications may have overlapped in production and the A-230 been an option during the early-'70's overlap.
I don't know when the A-230 ended as the book was a 1977 edition and I remember the base Volare column shift 3-speeds then. It may have been available in the truck applications until the early 1980's?
The 1976 Motor Truck Repair Manual covers the 'Own Make' (New Process) transmissions for the lighter duty Dodge/Plymouth A/B vans and D/W pickups. These A-230/A-250 transmissions were basically passenger car-type transmissions. They mention an A-390 and refer you to the 3-speed trans. 1963-75 in the Ford chapter.
It also covers the heavy-duty Dodge truck transmissions like Fuller, Clark, Spicer and Warner. I don't know how specific a model application you need.
It gives basic rebuilding procedures and exploded component views. You may still be able to find a manual like this at a large public library in the backroom storage 'stacks'. Call or ask your librarian.
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