I'm doin research too.. But still having questions..
for wastegate, I dont know about revhard, just email them.
BOV, it just lets the boost go out into the atmospher with that pss sound, recirculateing valve serves the same function but recirculate the extra boost back into intake without the sound. rv's are cheaper I think..
boost controller, wait a couple of months and I'll tell you.. most important gauges are EGT (coolant temp???), boost, and a/f. good point skippin on the boost gauge.. I dunno.
lotta peeps use apexi injectors.. two kinds, side and top feed, side feed for KA's I think.
email nsport or something.
As much as I hate to say it, but Freshalloy forums are much more knowledge and useful than zilvia.. Go search the topic on there and you'll know everything. still tryin to fiqure out what EGT is tho.. mmm.. <img src="http://www.zilvia.net/f/iB_html/non-cgi/emoticons/eh.gif" border="0" valign="absmiddle" alt=':eh:'>