Best option, rebuild my cadillac 429, or 472?

I have a 66 cadillac deville, and I plan to have the stock 429 engine and trans rebuilt this year. It runs, but it is starting to knock alittle bit. Also the ****** is leaking a little fluid. I have a guy selling a 1968 472 motor and trans for $350. He says it is good and was running when pulled out(but thats just what he said).
Would it be a better option to rebuild my stock 429 engine and trans, or should I buy this 472 and trans and have that rebuilt and thrown into my car instead? I hear around that parts are more steadly available for the 472. The image is of the 472 and trans that is forsale.

 

I would stick with the 429. They are really good motors and get decent milage. You wont have to change anything either. The 429 has shaft rockers whitch is a big plus over the 472. If the 472 is a later one it could be low compression smog motor. Im a big fan of the 429. there arent many aftermarket speed parts for them,but in stock form they have plenty of torque.Itl cruise that caddy at 100 all day long.
FEDER

 

Id buy a complete running 472 with ****** for 350.oo all day.


As for what you should do, thats harder to say.
"Knock a little bit" and "****** leaking a little fluid" doesnt automatically mean they need a rebuild in my book.

Have you verified you need a complete rebuild on the 429 by any other means? Comperssion test, leak down test? Anything like that? And where is your ****** leaking from that make you feel it needs a rebuild?

Id try to keep the 429 in there if I could.

 

pretty good thread on here already (but this is NOT one of those common HAMBer "do a search you FNG ***** replies!)

.....so many more parts available for the 472/500.

http://www.jalopyjournal.com/forum/showthread.php?t=119269

Were they using the TH400 already by 66? If not, throw that hydramatic off a bridge and get an adapter plate!

 

To be honest, I don't really know much about mechanical work. The engine runs, and I can cruise all day at 80mph on the freeway no problem. It has a knocking noise, and I'm not too sure what it is comming from. Maybe I just need a tune up? I'm not too sure about the trans either, lol. It shifts smooth and everything, it just leaves red fluids on the floor where ever its park. I just figured I have everything rebuilt so I know its all new, then just keep up with mantenice from there.

I saw the 472 forsale for $350, so I was just wondering if I should of jumped on it.

 

Had a 67 Deville Convert with a tired 429. Loved the styling of the car. Just wished I had found a 68 instead. They look identical but have the 472. Was planning on a transplant to a 472/500 but sold the car first. Too many one of issues with the 429 and no real performance options. Oil pumps are one example.

 

After putting three 429s (one a factory drop in) in my 65 Caddy convertable I decided to go to a 472. If memory serves me I positioned the ****** on the mount and drilled a couple of holes in the crossmember, took off the thermostatic fan, put on an appropriate fan spacer with flex fan. That was in 1995 and it still runs great.