Here's a pic of the same cylinder as the first pic with the valve seats cut and the correct 2.20/1.81 valves. Plenty of space between them.

And a pic of the damaged cylinder all done.
Not super pretty, but it should work okay.

As mentioned previously, these heads already had some port work done to them, otherwise it wouldn't have paid to fix it.
To fix the one head was about 1/2-2/3's the cost of buying a new head and porting it an amount equal to what was done already.

Finished product(not the damaged cylinder, although I think it would be pretty much the same), still std port window:

Lift---------in/ex
.100---73.1/ 56.5
.200--151.2/97.6
.300--205.7/139.5
.400--260.6/173.2
.500--302.9/205.4
.550--316.7/215.4
.600--324.2/224.9
.650--334.7/228.6
.700--342.2/235.1
.750--342.9/238.8


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