460 Bolts and carb tune

Question, im getting rid of my new hedman headers (always leak!!) and putting truck exhaust manifolds back on also new oli pan and intake, would you use the stock fasteners or aftermarket? And if aftermarket which type? AND with the Holley 750 double Pumper carb what size idle and midrange (tow cruise rpm 2000 to 2200 rpm hiway) would you consider?? The Original carb jets are way off you can smell the gas oline just almost running out the exhaust .Thanx Mike

Where are they leaking?

Its a original 1984 never been outa truck. had a bad leak would lose 6 litres oil (rear crank seal)then stopped leaking again (cold here now winter time its a year round driver) redoing heads ,back to truck exhaust manifolds. DONT want it to leak!! New rear seal ,fel pro gasket kit, new oil pan rocker cover gaskets and so on .I DONT want leaks. Also engine builder told me that the valve guide seals that come with the fel pro kit(black rubber type ) arent very good? Anyhow I figure nows the time to do some fastener changes if it will assist in making it leak free. Thanx Schmitty this is my first car engine. Im already thinking o=f a 11 to 1 460 on propane to build after this oned done for a future project, Thanx for youre reply Mike