I found out the 84 is odd in several ways. I bought it with a bad 5 speed transmission. He had a rebuild kit he threw in, and a new main input shaft/gear also. But when I tore the trans on down I found the front gear on the bottom counter gear assembly was missing some teeth also. That and some missing detent pieces left me discouraged and not wanted to mess with it. Looking around I found out the 84 5 speed is an oddball, it's a Toyo Koygo, but it has the external slave for the clutch, a one year only deal. So that makes it very difficult to find a used trans for it.
Doing research, mainly on this site, they warned that all the different transmissions where different lengths. The 5 speed in the 86 ranger was a F146 Mitsubishi. I did some preliminary measuring, and came away scratching my head, they seemed to be very close, pretty much the same from the bell to the transfer case flange. So I decided to do the swap, it bolted right in. You do have to use the 2.9 flywheel and clutch on the 2.8, but other than that, went right in. I even took the ranger clutch system out complete, not taking anything apart. The hard part was snaking it up through beside the engine as I was moving the trans in place, but I got it, and didn't even have to bleed it.
Another thing I was worried about, the ranger had the electronic transfer case, the 84 had the manual transfer case. Did the electronic transfer case adapter have the required threaded holes to mount the manual transfer case shifter properly. Sure did, just had to dig the road dirt out of them, shifter bolted right in place.