Unless the engine has been replaced, it is either a 235 or a 261. 270 was a GMC only truck engine and usually only found 1&1/2 ton or larger. To find out whether it is a 235 or 261, look above the starter on the side of the block. If there are two raised marks resembling captain's bars, then it is a 261. Otherwise, it's a 235. The 270 has a different valve cover with two nuts on top to fasten it down. It also says GMC on top of the valve cover.
Unless the engine has been replaced, it is either a 235 or a 261. 270 was a GMC only truck engine and usually only found 1&1/2 ton or larger. To find out whether it is a 235 or 261, look above the starter on the side of the block. If there are two raised marks resembling captain's bars, then it is a 261. Otherwise, it's a 235. The 270 has a different valve cover with two nuts on top to fasten it down. It also says GMC on top of the valve cover.
You gotta go take that and fix it up. You own sail something like that and you're gonna be fixed up and coming back
I have like over 40 old trucks