2000 Silverado missing problem

[JWI Racecars]

Hello everyone, I have a problem with my 2000 Silverado with a 4.3 V6 and 5 speed trans.
The problem is a intermitent misfire/ engine cut out.
I replaced the plugs, wires, cap, rotor, coil, ign module, and even tried a new computer. then I took it to a GM dealership and they said Crank position sensor... so I put one of those in too..... still missed, so I took it back and they said there was a bulletin about the crank position sensor contacting the reluctor wheel in the front timing cover. they said it makes the computer think you're spinning like 10,000 rpm and cuts the fuel pump out, They said to replace the cover or shim the sensor.. So I let them shim the sensor.. worked long enough for me to pay the bill and make it home. started again... so I pulled the sensor and replaced the shim they installed (rubber o-ring) with a spacer I machined out of aluminum.. worked OK but I still have a slight chug/ miss... It kinda feels like when you're fuel filter gets clogged on a Carburated car....(replaced fuel filter too)


Sorry this post is so long... But I am frustrated to say the least... any thoughts????

Thanks for any help,
Joe