Mk-13 has a much smaller footprint than Sea Dart and the Mk-8 is comparable to the Mk-45.
I have an incomplete model of an RAN Type 42 somewhere; I stuffed the paint up and need to redo it.
It had a Mk-45 5", a Mk-13 with appropriate directors for SM-1 and i built a new hanger for two Sea King, similar to ARA Hercules in her current configuration.
https://en.wikipedia.org/wiki/ARA_Hércules_(B-52)By Colección Martín Otero - In the Atlantic South, <a href="
https://creativecommons.org/licenses/by/2.5" title="Creative Commons Attribution 2.5">CC BY 2.5</a>, <a href="
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While quite doable, it was a bit wasteful too, as Sea Dart was a superior missile to SM-1MR.
My WIFF that I have yet to attempt is an evolved Type 22 with Tartar (probably Mk-13, maybe Mk-26) inserted in a hull plug between the funnel and hangar. Either retaining Seawolf, or perhaps replacing it with a Mk-29 and Sea Sparrow. This would have been instead of DDL / FFG-07. A further development would have been a Batch 2 built in the 90s with Mk-41s replacing both the Mk-13/26 and the Mk-29.
In this same AU a Type 21 with US systems, i.e. Mk-29 Sea Sparrow and Harpoon, would have been built as a GPF/Sloop, supplementing the high-end combatants. There would have been no patrol boats in this scenario, rather a small force of reserve training vessels and a couple of FAC for training and operational evaluation / trials.