Ok so i was talking to my brother today about the little valve tap that i had that was little until i put Zmax in there and made it worse but he told me that when me and him worked at this engine shop in philly that the 305 heads and the 350 heads are the same i got to thinking that i wanna try to swap the 305's for th 350's but i want to make sure that i dont need to be doing any major work b/c i have little time.So my ? is do i have to do anything else or can i just put them on?

well you'd need to find out which exact heads they are in the first place. can't think of any 305 heads that were the same as the 350's heads right now, only thing that hits my mind is you can use the corvette's 350 (L98) HO aluminium heads on a 305 on a real good price/performance ratio, but they do require some mods. this has been discussed on this board quite a few times, you might want to use the search function once you find out what heads you're looking at.