scotts60,
You might want to specify the year of the 235 block you want to use in your 1953 truck.
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The "848" head was produced from 1956-1962 (it is quite common, and it works on any 18-head-bolt 235 block) and it resulted in higher compression. These heads seem to be prone to developing cracks. The "848" head can also be used on a modified 261 block
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A slightly higher lift cam was used on 261s and on many 235s, depending on the model/year/application of the 235. That cam be used in any high-pressure-oil-system 235.
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Do not overdo the carburetor(s). The simple-minded method of matching carb/carbs to a Stovebolt-6 engine is to match CFM ratings of carb/carbs and the engine. CFM is not a readily available parameter, so you could try to roughly match the cubic inches of the 235 engine and cubic inches of the engine that the carburetor(s) came out of.
As suggested in other posts above, you cannot easily/inexpensively get a lot of additional power out of a Stovebolt engine; but, you can get a noticeable improvement with careful changes.
It seems that many people get rough-running souped-up stovebolt-six-engines caused by adding "too much carburetion". For example: using two 235 carbs on a 235 or two 261 carbs on a 261. (I have first hand experience).
It also possible to have "too little carburetion", resulting in a fuel-starved poorer-performing engine (I have first-hand experience with Landon's dual Carter-Weber on an wide-bore 261).
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It does not look as cool as multiple carbs, but you could look for an appropriate-size two-barrel carburetor and/or a carburetor with adjustable main jet/jets. GMC Zenith Carburetors could be used - they are a little uncommon and they can be expensive (because they are rarer and quite good carburetors - making them worth more).
