Originally Posted by GregM
What would you...do?
$700 is the basement starting price for custom pistons. Unfortunately, the 429 has almost zero piston options for lowering compression. The 460, on the other hand, has endless pistons options and this includes dished pistons.
My advice is simple, and I strongly recommend that you take it: Rebuild the engine with a 460 crankshaft.
This way, you'll get a free 37 cubes (.030" over is a 466) and plenty of dished pistons from which to choose (for much less than $700). I strongy recommend a "D"-shaped piston dish. Also, the CJ heads are way, WAY too big for the little 429, so you will also have much better throttle response with those heads atop a 460. The 429 would be a complete dog of a motor with low compresison.