I am not being clear. the missing screws I  am speaking  about  ar the metering  plat behind the secondary float cover. 1 screw was loose and ready to fall out. tightened all of them
when I had the float cover off noticed the rubber seal on the gas feed tube cut up from assembly. fished out the particles,and checked  float valve. will install later and see how it works
the  missing screws holding the throttle plate,i guess  don't  matter. have another  older Holley  they are missing as well
thanks to you all for the help.. next time will try to be more disrupted as to the issue.  won't betraying the truck for a while as we got 1ft of snow hear last night, southern  Vancouver Island(Shawnigan  lake)

The Holleys we use for racing only are modified by a shop for our application and always leave out the center screw on the bottom.  

56 Vic, B'Ville 200 MPH Club Member, So Cal.

I'll have to take a look at my 4150 (still in box) for the 2 missing screws. Why would Holley tap the carburetor for screws but then exclude them? 

In the past, I have experienced issues with either loose screws or warpage at the throttle plate to main body on the 4150/4160 Holleys.  Any air leaks at that particular gasket makes for a lean idle mixture and makes it difficult to run without the choke being applied.  On the older carburetors, there were eight screws but many of the newer ones only come with six while leaving two of the threaded holes just without the screws.  Adding those two screws can potentially make the difference between a ‘too lean’ a carburetor at idle and one that runs okay.

Lorena, Texas (South of Waco)

I've had good luck with a couple of new Holley's that I bought directly from Holley. It's also my understanding that the remanufactured carbs they offer are good and cheaper than new. Not sure if getting shipping to Canada is an issue or not.

having greatff with I purchased  from amezon. poor idea,will run fine on warmup choke, then idels well for20seconds,then stalls. no external vacuum leaks. it runs fine at 1000 rpm
after a good run  ideas better at800 rpm.  as I had run out of amazons warranty, and they claimed no stock. month latter purchased another for500cnadian,brawler  model very shiny. installed  2ndarets  poured out gas. at secondary.  removed  float cover, found  several screws loose.(was told these carbs are assembled in usa..the company  amezon sells for  agreed to reimburse me  for  the amount they got from amezon. considerably less than I paid amezon. I fixed the loos screws ,but reluctant to use the 2nd carb.
 the gas we get hear  in canada in summer months  is poor at best. any  ideas.the 292 is like new, burns no oil pulls good,,no vacuum leaks.
ANY IDEAS,  CLIFF  AT 55METEOR