1.2.5 to 1.3

Last night I tried to upgrade my clients huge (1.6 mil posts) BB to no good end.

I followed the instructions here: http://punbb.informer.com/wiki/punbb13/ … _punbb_1.2

and ended up after about 1.5 minutes of browser spin with a white page and this url
http://www.sitename.com/forum/admin/db_ … art+update

I also tried adjusting the

define('PER_PAGE', 300);

bit of db_update.php to 100 all the way down to 10 with no result.

I tried refreshing this page many times to no avail.  Watching top I can see mysql working hard but then it peters out a bit after the page goes blank.  I think i am likely just tired and brain fried and making a stupid mistake here.  I would appreciate any help you guys could offer.

Thanks!