I think whatever you decide next, you'd do well to read all of George P's post on the subject; there are savings not to be made as well as limits not to be exceeded even if you can easily find all the parts that allow you to go beyond the reasonable for reliability.
https://pantera.infopop.cc/top...d-performance-tuning
https://pantera.infopop.cc/top...mber-4v-heads-q-code
https://pantera.infopop.cc/topic/351C-super-stock
https://pantera.infopop.cc/top...er-vs-closed-chamber
https://pantera.infopop.cc/top...using-all-ford-parts
https://pantera.infopop.cc/top...640#1598208419963640
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