78 Step Side 6 cylinder 4 speed

[novapwr]

Hey guys and gals. Just acquired this old 78 4x4 step side with the six cylinder truck, pretty solid but transfer case and tranny look to be both leaking lube pretty good. The guy I bought it from only used it to plow with then it sat. Can you tell me the model transfer case I have and tranny? The transfer case has low and hi range and the tranny has the granny gear. Both are very quiet and work great. How hard is it to replace the seals on these. Tranny looks pretty heavy. Am I looking at a very expensive repair if only seals are bad? Pretty sure they would need removed. I did do a search but did not find the info I needed. Thanks .