Recommendations for trans fluid??

I always run valvoline dex/merc. Never an issue. You can run type f too, it won't hurt anything. Some guys run dex/merc with a quart or two of type f mixed in with no issues. These old trans are not picky on fluid like a newer trans. I've ran them on pure 30 weight motor oil in a pinch with zero issues. Literally pick the cheapest, quality brand and call it good. Just service and adjust it when it needs it.