Hello and thanks to your replies!
I haven't gotten around to try that mod out, but if i do, i will post a reply here.
I have a 2600JR PAL version, with the large rainbow and iirc the circuit board was the same as on the web page.
I bought mine from a fleamarket and it was missing the original PSU so i can't tell what those should look like.
@donutty: if you make an article, please post here, i guess it would be interresting reading
Regards
Jani