Too Doo or not Too Doo

Was talking to my cousin last night and he said he'd trade me a LD340 with heads and everything it just needs rebuilt and bored for something of mine (don't know what yet) and he also said that he would trade me my built slant six for his V8 Kmember because hes wanting to build the slant alittle more and run that in his duster....So do you think i should do the swap and dump money into rebuilding the 340 and running it in my duster. or should i just keep my slant and not spend as much? I'm getting the 340 either way i'm just thinking i should drop it in my duster. what are your opinions??