To date, I haven't been able to figure out the difference, if any. And, nobody has reported any issues using the "late" VB with an "early" intermediate plate. I'd go ahead and install the late VB in the early transmission.
Before installing, I always recommend removing all side plates of the VB to remove all springs and inspect for damage / broken springs. It's rare, but you don't want to have to repeat this job if it doesn't shift quite right. I'd also replace both the K1 and K2 spring trains & pistons with new since the parts are available and (relatively) inexpensive.