No real need to take the 5EFHE out and put in a 4E. Just get a starlet EP82 exhaust manifold, CT9 Turbo, and dump pipe and away you go (after wiring and plumbing of course.
Yeah they are beautiful cars, the pic in my avatar is my Sera. About 190 of us Sera owners have a forum that is a LOT more active than here (when it comes to Seras: http://www.omicron.uk.com/sera/forum/index.php
I desperately need a CT9 turbo (and flanges etc) from an EP82. This is a very urgent thing so if anyone can help with this please contact me ezekial_walters@hotmail.com