I agree with Mark here: you should address the fuel tank. There are several points of weakness with the stock tank: rust corrosion, the old fuel sock sloshing around, the banjo fitting ...
I addressed mine a few years back and was very happy with the end result. The project is chronicled (with pictures) at this link.
Best of luck with the engine rebuild! Just remember to make sure she goes FASTER with the new powerplant!!!
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