Josh,

When it comes to rebuilding on a shoestring, you simply won't know where you can get away with very little until you measure, measure, measure.

In regards to the cylinder block decking: The OEM pistons in the 1973 429 are a whopping 0.040" down in the hole at TDC! You would be very wise to deck the block so as to effectively bring the pistons closer to TDC. With the OEM pistons, it may be necessary to deck as much as 0.040" off the deck BUT I recommend that you bring the deck height down to just to 10.300", 10.295" minimum. The OEM D1VE blck of the 1973 429 is usually found to be about 10.322"-10.325", and the reason I suggest decking down to just 10.295"-10.300" is because many aftermarket pistons are manufactured with 10.300" in mind, so leave your future options open. Further, decking down to 10.286" (<---OEM piston deck height) may cause a need for machining in other areas that I won't get into here and now.

The main reason for decking the block in this particular case is to gain better control of detonation. The cost is typically about $75-$100 to deck the block and worth every penny.

Paul