Trying to build power....225 step by step help

Hi Guys im trying something new...im more confortable to post here than any place else on the web : just bough a 1970 deputy challenger 225 3 speed....needs a total resto, but waa thinking to do something cool with it...and built a kind of 225 sleeper e bodie..i have no Clue ( so used to small blocks ) ..were to start and what to do with a 225, would like to run efi , Uncle tony garage as good infos , but is there sites or simple infos to go get 250-300 hp with a slant in a light body, thx guys !!!

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