Sidehill,
With the Ford 300 you get a huge head start for hot rodding, versus the 292. In other words it doesn't take as much work to get the same results in terms of power numbers in the Ford as it does the Chevy. The biggest factor is the head design.
The Ford factory head (with its true twelve port design and unrestricted intake flow) will obviously hotrod up better without major mods than the Chevy. To get optimum power and flow from the Chevy head the intake boss in the siamezed factory intake MUST be removed and a (bolt in, brazed or epoxied) lump port must be created. The lump port head has been done and re-done many times successfully with excellent results, but the work is hardly a task for the occasional enthusiast (certainly not doable for a novice).
The Chevy 292s stock piston design is a liability too. The .300 recessed deep dish head and resulting 8.0-to-1 compression ratio is hardly what you want for impressive power (except for certain forced air applications where a low CR is desirable). If the low CR isn't bad enough, the factory cast piston is also extremely heavy. The weight is actually probably a worse liability than the CR because the compression ratio can be raised through other means fairly easily (shaving head, etc.). Lightening the weight of the factory pistons while maintaining a balanced overall drivetrain is expert work.
But the biggest and most important advantage the Ford has is the factory head design. Hands down the Ford wins.
-magic mike-
