Dude, you have had terrible luck finding engines. I have 3 good engines here in the garage...running 170, freshly built 225 short block and a running 225...Did not have any of the problems you have found on my last 4 slant builds.
Yeah it is what it is but it does suck. The correct way would have been pull the stock running engine in the dart currently and rebuild that. But I did not want the car down that long so I wanted to build one, have it on the stand, then do the old swap-a-roo in a weekend. I guess wishful thinking. But I can tell you the one problem with ever engine that has taken them out..........Fuel pump leaking fuel into the oil and thinning it out. Every single one had the same problem. So boys and girls change that fuel pump ha ha ha ha.