The 429 was a good 60s engine. But it had problems with the oil pump wearing in the aluminum front cover (no new parts available). I personally prefer a mid 70s engine with HEI, valve rotators, ability to run fine on unleaded gas, and no pump problem, Bruce Roe
If that car has been sitting in grass for a considerable time, it will have a lot of rust underneath. If it's a project you want to tackle, get a look at it underneath the body. How many miles on it ?? A powerwasher is the first tool you will need in the engine compartment.
The oil pump that Bruce mentioned is on the right side/bottom of the timing cover, and the impellers (gears) are removable, if you want to inspect the housing they are in, for wear etc. The impellers may be available, don't know, but as Bruce said, the timing cover isn't.
Of course an engine change/update to a later type has been done by folks on this forum.
she got sold. i wanted the motor for something else, and i need something with performace parts available. and the underside is pretty much shot. rear frame was gone, fender wells looked like swiss cheese. but the interior was really nice. i was surprised. got my eyes on another big block now. thanks for all the input and help.