81 to 84 head swap????

I picked up a 1984 doge d50 with a 2.6 g54b with a cracked head i spare head for my 81 2.6 g54b. will my 81 head work on my 84???

Short answer - yes. Just do a quick visual inspection to compare all the manifold mounting studs and that will be enough to tell you for sure. It's when you try to play mix and match valvetrain parts between flat tappet and hydraulic heads you get into trouble.

the intake manifolds are different - 81 head should have 2 studs by the thermostat, the 84 has 1 near thermostat, one under intake, and the whole bottom row of studs are in different places. otherwise it will work.