Upgrading to XP Pro from XP Home with SP2 installed

I had planned to upgrade from XP Home to Pro later this year. However, today
I learned that a national computer chain has a one-week sale on XP Pro
Upgrade at a substantial discount. So I bought a copy.

My system (a Dell Inspiron 8200 notebook) has XP Home installed. Last night,
before I was aware of the XP Pro Upgrade sale, I installed SP2 from CD-ROM.
Everything went smoothly and so far there have been no problems.

However, I now have to decide how to upgrade to XP Pro. I assume that the XP
Pro Upgrade does NOT include SP2.

So, I can:

1 Remove SP2, install the XP Pro upgrade, and then install SP2 again. I've
read the KB article about removing SP2, and it's been only a day since I
installed it.

2 Install the XP Pro Upgrade "over" XP Home SP2 and then presumably install
SP2 once again.

Method 2 would probably be quicker, but I'm inclined to go with Method 1.

What do you think?

Also, there is remarkably little information that I could find about
upgrading from XP Home to Pro. Nearly everything that I could locate had to
do with upgrading from an earlier Windows version. Is there anything special
to watch out for? Any KB articles that I missed?

Thanks for any help.