Windsor or Cleveland Cam

All the 302"HO's" use a 351 firing order from the factory and they had dual plane intakes. The firing order was changed because the 302 fires on two adjacent cylinder simultaneously causing a severe load on the main bearings.

"If you look at the dual plain intake on a windsor compared to a 302 you will see that the plains are the oboist way that is because of the firing order . Ford tried to keep the intake charges on two ajsent cylinder's on different plains so the don't rob the second one of a charge"

Beg to differ with you here on your statement here about the intake manifold causing the firing order to be change. The intakes maybe different, but that doesn't change the firing order. The camshaft dictates which firing order.

If you have the time and energy, take your two intake configurations you're describing above. You can run a 302 or a 351W cam in both of them. BUT, the firing order will be different between the 302 [non HO] and 351W. You can interchange cams, just change the firing order.

Ford changed the firing order on the 351W when it was introduced in 1969 to help with the load on the crank. Sorry, I'm not an engineer, but have read that numorous times. The 302 HO has the 351W firing order, because Ford used its 351W marine cam in the 302 for more power. So the firing order had to change to the 351W.