Another way would be to install a set of used front springs (from a 'salvage yard') & see how you like the truck stock, with the 292 engine.
Then make the 'upgrade decisions' later, if needed.
Don't put to much on your plate.
BTW: Using the exhaust system I suggested is a "tried & true" method that began in the 1950s. It doesn't need/require proof from/for anyone as it is 'standard' in the industry.
Many of these 'exhaust acessories' you see in Hot Rod catalogs and hobby shops are just there as a marketing ploy to generate revenue(s). They do little, if anything in the 'real world'.
