Don't know if this is a simple pleasure or what really

A few years back I did my family genealogy, but it all came to a grinding halt back in 2010 as I didn't have the time to go trawling through record offices. Then just before Christmas, I got an email from an old School friend, who was very worried because he'd been doing his family tree and comparing it to mine he was disturbed to find we possibly shared a common ancestor, making us 4th cousins. He thought that my family tree must be wrong as it had way too many people in it - I just used to have to much time on my hands - and wondered if I'd taken an Ancestry DNA test as he had, and he wanted to rule out being related to me.
Now, I hadn't had a DNA test as they are too pricy, but I'd had a better than expected Christmas bonus and Ancestry had money off their tests at the time so I did one.
I now have the results and we are related! This will piss him off mightily!!!!! The test says at 5th to 8th cousin level though, which is a bit more remote than thought, but even if I'm wrong on that line of descent, which is on my dad's side, I'm also descended from the same family on my mum's side from a generation further back.
I've just got to think of the best wording to tell him to upset him the most...
FWIW, my ancestry is:
68% Great Britain (Mainly East Mids - as I'd expect)
13% Scandinavian
10% Irish (mainly Connacht - as I'd expect)
5% Iberian
2% Southern Europe
1% Finland/NW Russia
1% Caucasus