Quick Help with 83' gmc

[RapidRide2]

I have spotted a seemingly really clean 83' gmc 1/2 ton 2wd 8 ft. bed. 305,, 700r-4(in good working order) pwr windows locksA/C. no rust Mississippi 2 owner truck. My questions are does this truck have any type of basic computer for timing or carb solenoids?? If not i guess it would have a regular h.e.i correct??? Does anyone know what gear ratios were available in 83' in 1/2 tons?? When i inspect the truck what are some things to look for on these 83's as far as body and mechanical???? Does anyone know what m.p.g. a decent tune up with the 305 single cab 1/2 ton w/overdrive should get????Thanks a million to all who can help. Matt