1998 Blazer not cranking

My Blazer is not cranking over, I discovered yesterday that I have raw fuel in the cylinders so I have either a leaking FPR, fuel body, or both. I had some other
battery, connections issues but I resolved those items yesterday, after I did that I learned about the fuel in in the cylinders. I pulled a couple plugs and fuel drained out. So I am looking at pulling the upper intake manifold off and see what is going on. If I need to replace the spider I intend to upgrade to the newer MFI, I have read a lot of threads regarding that elsewhere. Has anybody done that? I am looking at the Standard Motor products Fj503. One website says that I need a bracket and gasket which is not included which is not included. One posting I read the poster says everything you need is included even though the description says otherwise. So my question.
Has anyone purchased the SMP FJ503 and has it included everything you needed? (bracket and gasket)
Thanks for any info. I also have an e-mail into GM Parts Direct.

Your 1998 4.3L has Central Sequential Fuel Injection, (CSFI). The TSB retro-fit changes the system to Central Multiport Fuel Injection, (CMFI) which was used from 1991 to 1995 and is less fuel efficient. Before making the change, you might want to diagnose the problem with your current system. It will most likely be far less expensive to repair your CSFI.

Start by checking fuel pressure and leakdown. Key on, engine off, fuel pump running: Fuel pressure must be 60psi to 66psi and must remain above 55psi for 3 to 5 minutes after the pump shuts off.