[84LX89GT]

Why yes you can! The 429 is related to the 460 and there are tons of swap headers, oil pans, motor mounts, etc. etc. for your engine. Check google or other search engines for info on swapping a 460 into a Fox body mustang and it'll come up with a lot of stuff. Summit racing and Jegs even sell stuff in their mustang sections for 460 swaps. Swapping a 460 is alot more common because of how many 460's were made, but it all applies to the 429.
You have it easy, i'm doing a 400 (m-block) swap into my stang (will be 406), and there is only one thing that i've found for that swap, which i believe is a milodon fox-mustang swap oil pan (351C 351M/400). i will need custom headers (if i use headers) and oil pan, but most of it will be welder modification.
Good luck if you decide to do the swap. Post what you've done!