A turbo on these low speed poor breathing engine is a great idea,and not too difficult as you say.I set up a Holley 2300 on a stock intake on a 261 Chevy(larger truck version of the 235)The carb is around 280 cfm,was used on a IHC 266 V-8 engine.I opened up the top of the manifold,made a mounting adapter from a piece of resin board,drilled and tapped holes for mounting, made up a linkage.There more details,but if you mess with turbo, this would be a piece of cake costing pocket change.Oh, a 2 bbl is rated different than a 4bbl,so the 280 cfm I used is marketed as 350 cfm.I previously had installed a 2-1/2 inch single pipe on the stock exhaust with a cheap turbo muffler.
The engine has far better rsponse and power and actually gets slightly better fuel mileage.I tried a 2 bbl on a funnel adapter,wasn't worth the effort.
The stock Rochester is a sorry carb even compared to other single barrels of the day, a Carter yf or Holly 1904 single barrel is an improvement.
140 hp rating was on a factory dyno with no assesories and everything absolutely perfect, real word power at less than 4000 rpm is around 110 hp
