The funnels in the kits are too short for either ship and are really better replaced with tubing. From Kronma's post you can find the width of the funnels.
http://www.shipmodels.info/mws_forum/viewtopic.php?f=47&t=12304&start=140
Borodino's funnels were 13 ft 1+15/16 inch wide and Orel's funnels were 14 ft wide. I thought Borodino's funnels were slimmer than Orel and the others, but I had no proof. Thankfully Kronma supplied it. I haven't worked out the correct height of the funnels, but Borodino's were shorter than Orel's.
There are many differences between these ships that are not reflected in the kit though.