I've been contemplating somethings similar as a project car myself. Won't be a complete stroll in the park, but worth it none the less.
For me personally, the 2j route isn't "special" enough for all the effort, it is just turning a gs300 (a rebadged aristo) into an aristo, which came in that guise. i.e. It is easier to buy an Aristo and put the gs300 sport bits on it to get the same overall result.
Having said that, more tuning options on the 2j.
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