I have the APEX kit on my 00 ex d16y8 and i'm pretty happy with it. The turbo is about T25 size but it's ball bearing so it has really fast spool up times. The manifold/downpipe fit like stock and all the charge piping/small hardware was also perfect. The only downside to this kit is that it doesn't have any fuel management, an intercooler, or a bov.

The greddy kit is also really good for the price, it includes pretty much all you need except a BOV. Everything fits well, is easy to install, and it uses a 15G turbo.

If you want a T3/T4 the Revhard and FMAX kits are okay, try and stay away from DRAG, some ppl have had problems with fitment problems. The lag on a t3/t4 turbo D16y8 can be kinda bad, i've heard of some people not reaching full boost till 5000 rpms.

You'll want a boost gauge, probably EGT, and an oil/fuel pressure if you like the security. You'll also need a BOV and probably a FMIC, i ran my kit at 5.5 pounds for a while without the FMIC though. The first two kits are internal wastegate and the t3/t4 kits are external and probably come with a deltagate, which you probalby want to upgrade to a tial. You don't really need an ignition yet although it wouldn't hurt, and you really should get a clutch cause it will start to slip sooner or later (i know from personal experience and went with an ACT HDSS)

Other than that, my advice is to get some 450cc DSM injectors and run the VAFC hack, don't even mess with the blue box/fmu unless you wanna stay around 5-6 pounds.