I've never seen a shroud with clips to hold it together but I haven't seen everything either.
Once it's bolted in, it's not going anywhere. If it was me, I'd probably just leave it alone.
I've fixed shrouds by cutting a piece of roof sheathing (thin sheetmetal) and JB welding it on the inside out of sight to bridge the gap and hold the two sides together.
That looks like it has good pitch.
That's a 17" fan in a shroud that will hold an 18" fan. Yes it will look tiny.
In post #26 you said "2947 Hayden clutch if I remember, and the 215/216 Mopar fan". I hate to say this but you might be going backward on your fan selection.
Rock Auto says Hayden 2747 for a HD clutch to fit a 69 Dart
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