Has anybody put a pair of big blocks where the 350's where.

no, but i made some research ,and i think 377 scorpions fit , but not larger than that ...

They had a 29 on here a while back in the classifieds that had a pair of big blocks in there. Looked like a tight fit!!

I dont see why they would not fit, It would just be VERY tight between the pipes. (and A$$ heavy)

Big blocks will definitely fit. the drives are mounted on 34" centers as I recall. It will be tight though. I used to have one and had the same thoughts. figured it all out and then bought a 33 instead.

Ever see a 29 fountain ( like a 27 with a beak)with the twin bb's? Looks like it's sinking more than a twin sb 29 scarab. I'd buy a bigger boat too!