Thanks, Pete,
I checked the specs manuals and now see that the 1/2 ton and 3/4 ton 4x4 was available in 1961, but in that year the 235 and 283 engines were used.
but not to say that the 261 hadn't been put in years ago' if it is a 261.
put a 261 in my 32 chev in about 62
ron