It appears that there is an aftermarket performance head available now...Yes on the 300 ford six.
If you have not seen or heard how that is done your motorhead card needs turned in.
And with a little in the know the LS GM bore spacing and bolt pattern are nearly identical and with some tweaking "Tweaking" used loosely here the LS head can sit on top of the 300" six and trump the old school tweaked Cleveland head setup.
Just for you.
Freaky Ford 300 Inline-Six Topped With Sliced-and-Diced Chevy LS Head
Hot-rodding is all about innovation, with this LS-headed Ford straight-six being a prime example.www.motortrend.com
I think Grumpy Jenkins did the first 300 with sectioned Cleveland heads.
Finally! A Performance Cylinder Head for Ford Six-Cylinders
The first look at Vintage Inlines’ new aluminum head for Ford six-cylinders.
www.motortrend.com