need engine help PLEAsE!! crisis

[hjalbert]

well, i was going to put new plugs, wires and all in the suburban, and went about doing this, while i was at it, i was going to adjust the rockers, one was lose and being annoying.i did that first, pur in new plugs, and wires.i went to crank it up and it turned over real fast but didnt fire, then i realied thatr i hadnt reconnected the positive lead to the dizzy. so i did that, and then when it fired i had a mettalic griinding noise., now, i tightened these rocker arms the way that chiltons said to, and that is to put it on number one, and tigten it till its harder to spin the ...lifter(think thats wahat its calle, or a push rod??), then do the ones for number one, and then to turn the crank 360 degrees and do the oens for those. and when i loojked and checked again, the number three exhaust one was lose, so i tightened it up again, and still have a mettalic noise whenever i try and start the truck, but if i disconnect the pso lead to the dizzy, it spins over just fine, no metal sound, i wonder what i could have done wrong?????? could overly tight rockers cause that? also, anyone know which feeler guage to use, and how to do it? it would seem to me to be more accurate then theri way. thanks alot, this is a crisis!