Brother Bow Tie

I have a 2000 gmc Topkick that has been rode hard and put away wet. Bought the truck to use around my property. Put a dump bed on used it for a while then the problems started. It ran really good when I got it then one day I noticed it had some coolant under the radiator, simple enough to fix, started looking for the leak but couldn’t find one. Was going to do some testing but before I got to it I had a catastrophic failure. I went to start it to move it and a rod came out the side of my oil pan. I’m guessing at this point the leak was due to blown head gasket putting pressure in the cooling system and maybe the last day it ran the number 7 cylinder got too much water in it and hydro locked causing the rod to break. Well after a lot of to do I ended up putting a Jasper replacement engine in. More problems. Cant find many new parts for this truck for instance, I wanted to put new fuel injectors in , I can get them but can’t get any thing else in the fuel injection system such as the fuel rails which are plastic and when removing them some of the little ears that hold the clips that hold the injectors broke off. Well I was able to get by with using some frigger riggin . Also wanted to put new intake but can’t get one. Reason is that one of the bolts that hold the filter housing broke off and just on and on with little things like that but the biggest problem I’m running into is that the wires are very brittle and so I have a lot of issues. I have had to overlay several wires from the sensors to the PCM. Just a lot of crap. So getting to my question I would really like to put an aftermarket fuel system on that would eliminate a lot of this stuff like maybe a Holley sniper or something like that. I can’t find anything that would seem to be a plug and play for my application. The truck has a 7.4 with an Allison 545 . Can anyone point me in the right direction or am I domed to riggin till the friggin end of time. Please help.