Complete newbie to woodworking here.

I've edge joined two small (150x300mm) pieces of Oak and the join is
solid. However I couldn't get them exactly square so they look like
(looking down the board):

+--------+
| +--------+
| | |
+--------+ |
+--------+

Given that I have a power planer and a half sheet orbital sander, what is
the recommended way of making these flat (it's not as bad as in the ASCII
art, but it is a 2 mm lip).

My options as I see it a

1)Start again and try to get it perfectly level - not really an option
because a)I'm on a tight budget (making a few of this item) and b)I don't
know if I'd get it any better if I tried again anyway.

2)Run the power planer on a 0 cutting depth in a direction from right to
left (as per the ASCII art above) to hopefully level the joint (it doesn't
matter too much to squareness/thickness, just needs to be smooth)

3)Sand the joint down, working it in big circles with a 60/80 grit, then a
100 grit then a 120 grit.


I'll need to sand it at a later stage anyway, but I don't know whether I'd
get a better finish doing it now or using a planer.

Cheers,


Andy