IT will depend on how you situate the engine and where you want the shifter to end up, how far from the firewall you want the engine (remember you'll want room to get to the distributor.) and how much clearance to the radiator and fan.
The Spicer plates are the easiest idea, but there are other ways to do it too, like making your own frame mounts, or buying a universal style crossmember from someone like Summit. The most important thing is getting everything where you want it and where it will work, and keeping the top of the intake where the carb bolts level or slightly angled backward.
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