Found this 383, worth it for my 65?

So my 65 GT has the slant six and automatic. I will be converting to v8 at some point. I’m very new to mopars and have been reading as much as I can. I came across this 383 for sale. From what I’ve read, it can fit, but it’s tight. What are your guys thoughts about this exact engine going in my 65? Or should I look for a 318 340 360 instead?

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