My favorite was 250\200s modded h2e adrenalin twin stock pumps ITP RR live tuned this was quite a few years ago..
But it had good power... Ran good ...pulled good...it was just a really nice DD setup...
The modded H2 is what i would go with the 19cm housing like Joe said..
I loved my H2 and even more when i had it modded.. Ran it with 250/200 for over 100k..
Not sure how that hx55 let go there a tuff turbo..
My nozzles, solenoids, and controller are (coolingmist).. this is who I would go with also..
I use the water for cooling proposes only not for a power adder.. so not sure on the power side I try to keep egts at 1450.. at the track
I say Run it.. not sure if you will have enough oil but monitor it and see.. also BP..And see what its doing..
And what i would do if the 400 nozzles. Are not working out go to some 2s
I would hope to see you in the 600+ a little..
Good luck withe the build... have fun with it..
I have a set of good injectors in the shop If you want them come get them..
That way if you need to get that truck sold..you can asap..
Just have you buyer send me some good cores..