This may sound really stupid but will LT1 heads work on an LO3 setup?

 

Only with a lot of work. The coolant passages on the heads would have to be filled in with aluminum plate, then welded, then drilled, then the whole head would have to be milled to make it smooth. new intake bolt holes would have to be drilled and new coolant passages too. I have the article on my website.

 

I THINK THERE WOULD BE SOME VALVE CONTACT WITH THE BORE DUE IT'S SMALL SIZE.
A BETTER SOLUTION FOR THE 305 MIGHT BE S/R TORQUER HEADS WHICH I HAVE FOR SALE AND I LIVE IN MEDINA.
YOU CAN CONTACT ME IF INTERESTED AT jimjohn@apk.net.
jimjohn

 

there won't be valve contact with the bore with the right size cam but those S/R heads would be a whole lot easier to put on.