Another 360 Build question thread...

J'a and 915's are 340/360 heads, there port size varies from year to year without much fan fare to bother with. Id like to see the pictires.
Suggesting a single plane maybe a bit premature. Basing a cam size on lift alone is t a good idea since a cam from Hugesengines tends to run higher lifts than normal vs. other cam manufacturers.

The mis-match between ports is of a low concern with smaller camshafts.