Before you choose what to do, take an actual look under the left side of your engine. There may be indeed a provision to mount a starter. I've seen more than 1 63 that had a starter mount provision and most 64s do too even though full size did not use it until 65.
If you have a starter provision, a 350-400-700 swap may be easier, and much smarter, than you may think.
I would really be reluctant to put any money in that rotohydramatic.
Steve
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