swaping in a 454 bbc

I am probably going to be swaping a 454 into my 77 chevy k10...it has a 400 sb in it right now but has been giving me so many problems....blow by, loss of compression...and i think think the block might even be cracked because of white smoke out of the pipes. My question is will I be able to just swap in the 454 without any fear of trashing the tranny...I have a th350 w/np 203 t-case. I have read abunch of threads saying that you need to beef up the th350 for people that have 600hp big blocks. But, I am not looking to drag my truck, I just figure if im gunna get another motor I might as well go with a big motor that is gunna sound mean. All I plan on doing is just boring out the block to get whatever lip is there and then just go with a basically stock piston, new gaskets and headers. Will this pretty much stock 454 be alright against my new/stock th350?

also I no that a truck is not a muscle car...but I am just trying to get my thread out there to get an answer...

Does a big block even mount onto a th350? I thought that if you had a big block you would have to have a th400 trans to fit...

I don't know anything about Chevies...

Unlike dodge chev uses the same behousing on big and sb trannies, a good th350 is capable of living behind a big block but in stock form its gonna be border line. If it was me I'd run it till it breaks and then beef it up.

Unlike dodge chev uses the same behousing on big and sb trannies, a good th350 is capable of living behind a big block but in stock form its gonna be border line. If it was me I'd run it till it breaks and then beef it up.

i agree completely...thats probably whats going to happen