Since you asked for opinions here goes;
As the others have mentions I wouldn't rebuild it now if the truck cant use it untill later.
However just because you can't turn it over by hand via the balancer it may still run somewhat. Does it still have a starter on it or manual transmission? I would invest a little more energy into trying to crank the motor you plan on using. If it cranks clean it and paint it. If it will not ever budge, clean it and paint it. Either way its not so dirty, and either works alittle or will require complete rebuild when times right. Put motor back on frame.
This is what I just did this weekend.
Im not sure whether I am gonna use this engine or not depends on the engine but I can get it to crank and thats all I know about it. My frame is ready for a engine but my truck is not so we met in the middle.
So I took this old motor which I don't know much about.
http://good-times.webshots.com/photo/2624480300100505384NwLtVNPrimed and Painted it.
http://good-times.webshots.com/photo/2186364580100505384byhfmUhttp://good-times.webshots.com/photo/2625808100100505384lvkDqfPut it back in truck.
http://good-times.webshots.com/photo/2940665950100505384cTdfezhttp://good-times.webshots.com/photo/2672998220100505384XvGujSI now feel that I can move forward to the cab work. If the motor works then great. If it doesn't, im only out one long saturday and 20 bucks in paint.
I want a fresh engine with possible waranty when the trucks absolute road ready.
