There are a couple guys here that have an extra L20a...
I'd get some custom pistons, run a Maxima N47 head with 39-39.5cc chambers an run it at about 11:1
Is this motor for street, strip, road racing, bonnevile flats or what?
I would not plan on using an E88 unless it is the one that is the same as the E31 240Z head. The 260Z E88 was pretty much the crappiest head other than having the biggest stock cam.
If you want a Maxima N47 head I have one I'd let go of...shoot me a pm about that one.