93 vs 90 Polaris exhaust manifold inner tubes

I don't know if/why my 93 Indy Trail Deluxe inner tubes have gaps and the 90 Indy 400 don't. Maybe those gaps had something to do with the poor seals with the blocks, gaskets and exhaust pipes. Top of first pic is my 93, along with second pic.

Should I hammer the heck out of those 93 inners to be flush with the main exhaust metal?

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93 vs 90 Polaris exhaust manifold inner tubes