I'm assuming that would be where your catalytic converter is supposed to go, you can buy one from the dealer/ parts store (expensive) or buy a test pipe on eBay which would be much cheaper, or you could have a muffler shop weld a piece of pipe in there but then it would be a PITA to remove your...
i know there are a few guys out there who drop evo 8/9 in 2gnt eclipses mated with 4g64 spyder transmissions not exactly sure how long those lasted in there though, and im not too savy on 1gs, but my opinion would be to just wait for a turbo trans so you dont have to do it twice.
you should still build some kind of boost even if your turbo has shaft play, and your boost gauge should be reading in vacuum while its running and not building boost not at zero psi, so is it climbing out of vacuum to only 0 psi or does it just read 0 boost all of the time?
on my first dsm 98 rs the washer bottle was in the engine bay (no rear wiper) right next to the brake fluid resevoir, pump is located on the bottom of that, in my GST the bottle and motors are in the trunk underneath the spare tire.
welcome to the dsm world. im in the tampa bay area myself, ive been looking for some dsm meets for a while its mostly hondas over here i might have to go check out orlando.