Hi, I recently purchased an '89 DB71T carry which I needed to replace the engine in due to the previous owner pulling it apart & leaving it in the weather. I have purchased another F5A to replace it, however I am finding that there are a few differences between the two engine's, even though they are both F5A's from carry's (as far as I've been told.) Some of the difference's I have noticed are the oil filter location is different, manifold's are different (I went to swap original manifold onto replacement engine & found it had vacuum runners in the head & the manifold?? Doesn't look like it can be swapped.) Can anyone shed any light on this or had similar issue's? Thanks.