318/360 questions

[charger72]

I have a 77 dodge truck that I am trying to figure out which motor I have but cant find any #'s on it. where should I look? also, I have some spare 318? heads, could I use them on my motor as I need to redo mine since the motor burns oil and smokes every now and then on start up. the spare head #'s are 0434 and 2843675  03(found on top of head by rocker arms).
Thanks, for any help.