Fuel delivery issue. 1996 Chevy C1500 Silverado 5.7l vortec engine, 2wd.

I have recently installed a new factory 5.7l engine in my truck. I also upgraded the spider injectors, new distributor, new crank and cam sensors, new knock sensors, new O2 sensors and new cats and exhaust. I am getting a code Po300 but I am sure I have that figured out. 1 of my main issues is with bank 2 cat. It is heating up to the point of glowing red., I can smell raw fuel even when cold and at idle. I can tell just from my nose that it is coming from bank 2. I have not checked LTFT and STFT readings as of yet but I am guessing this is not a vacuum leak as it is affecting only bank 2. So my question is what should I be looking for. By the way I am a DIY er I can usually figure most things out by myself but I really don't want to screw up a new motor. Hoping for guidance.

i would look at o2 sensors and make sure you dont have one thats stuck lean (reading will be bolow 450 mv) if its stuck itll keep dumping fuel in to try and get an o2 reaction.

also make sure you dont have an injector thats stuck open

Thanks for your response. I would assume the upstream Bank 2 sensor 1 would be the most likely suspect. I did disconnect the exhaust from the cats to rear of truck thinking the old muffler may have been clogged which I believe is where sensor 2 for bank 2 is located. As for a stuck open injector, how would you check for that on a vortec engine with the spider injectors system. Also could a leak from the exhaust manifold cause the system to add more fuel. I did use the old manifolds but new doughnuts.

So if the reading is less then 450 mv this would indicate a stuck open sensor. Just making sure I understood it correctly.

check fuel pressure at the schrader if it bleeds off the regulator or injectors are leaking or even the checke valve in the fuel pump. the fuel pressure should hold. secondly the o2 sensor doesnt become stuck open. front o2 sensors should switch between .1 and .9 on the scanner.

Ok , thanks for the help I will try and let you know my findings.

let us know! it sounds interesting