300/260 Head Swap?

[87-300E_in_NC]

Does anyone know (from experience) if a 300 head will work on a 260 block? I believe that the valves are too large and will hit the block (and I don't want to notch the block).

After my machine shop screwed up 2 (two) heads for my 260, all I have left is a 300 head and cam, not damaged and ready for valve guides and seals.

First head: Rocker arm towers were installed in reverse order (at machine shop) from front to rear, causing the cam to lock up and break in half after 10 minutes of run-time.

Second head: was not vatted and therefore oil deposits were left inside the rocker arm tower bolt holes, and four bolts backed out, causing damage to four cam lobes and their rocker arms.. (and now I'm sick again ).....so I have a 300 head that has no pits in the cam lobes that I would love to be able to bolt onto my 260 block....without modification to the block that is.

Some say that third time is the charm....all I want to do is drive my Benz to Canada and then to Miami without fearing that the head will have issues...again. Has anyone made this operation successful?