Can I "borrow" rocker arms from my '65 273 for my '71 340?

What is involved in replacing factory 1971 340 rocker arms with adjustable rocker arms from a 1965 two barrel 273 with a factory solid camshaft ? My 340 will still run the hydraulic camshaft, but I like the idea of being able to adjust the valve train after I deck the 340 block, mill the cylinder heads, etc., etc.