Thanks, guys. I’ll check out those exotic engines. The 230 Chev weighs about the same as a Datsun Z engine but the trans may be lighter than even the later, aluminum Powerglide. And overall simplicity will be an important consideration. I can rebuild a carburetor but not an ECU.
Will need to build the suspension first, but it’s good to know I can plan for a six. (I once stuffed a 280ZX engine into a Datsun 520 pickup but wasn’t able to complete the project.)