Oldtimelampshop,
With the SBC swap, you’ll have difficulty with the steering column interfering with the exhaust manifold and pipe routing, even if you shift the engine to the right. The limit is the frame rail and room for the right motor mount. You may need to graft in a rack & pinion setup for this reason. A Mopar V8 has the advantage that a 1960/1970 exhaust manifold can wrap around the steering column (also makes posters here less excitable). Any V8 is a tight squeeze between the radiator core support an firewall. You’ll have to modify both; the extend differs between early and late 1949 models and the water pump you choose. A 1970’s Challenger radiator fits within the core support with the top bar cut an welded 1” forward. You may need to modify the transmission tunnel if you plan to use an overdrive automatic. For sure you’ll need to modify the inner fenders and the wiring harness. Obviously, installing a V8 is more work than rebuilding the L6, but could be less costly depending on your sourcing. Please post pix of your progress.