Rebuilt top end of engine now carb idles much higher?Please help

It's exactly the same just one crank revolution later.
Your firing order is 18436572
That is to say;
1843 on the first revolution, and
6572 on the second.
As you can see, 1 and 6 are both at TDC at the same time; one is on compression, while the other is on split overlap, the period when both valves are slightly open.
And the same goes for 8/5, 4/7, and 3/2.

If you had a slanty, the firing order is 153624.
153 over
624, there are your paired cylinders again.

A four cylinder with 1342;
13 over
42; same deal

It's always the same on 4-strokes; first half of the firing order over second half, reveals the paired cylinders.

Hope that was helpful