I like the boxed in lower rad support as well. Great minds think alike. I did a similar job w 2x3 boxed steel, and notched out and reboxed in the notch with the piece i cut out, by flipping the cut out piece over and reinstalling it with a couple end plates. this way the radiator can sit down in there and the lower support could still tuck up in tight. Then i trimmed down the original sheetmetal lower support and fit the top of it back in. And yes theres a crap ton of spotwelds holding that cheesy piece o crap in there. Dont forget your drain holes. I did mine w a 3/4" blair cutter.
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That a good idea, like what you have done there. Like seeing different variations of modifications, it amazes me how talented people are.
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