I need to replace both seats in a Penobscot 16. Most replacement seats are 8.5" center to center, but the measurements for my canoe is 8.75". So it looks to be 1/8" off for each side- is that a big deal? Should I seek out the exact specifications or will drilling them out not perfectly centered make a difference?
You’ll be fine if you just use your old seats for drilling templates. Seat frames are beefy enough that having holes 1/8 outboard from ideal won’t matter.
Just fyi edscanoe.com sells Old Town style replacement seats. In my experience his stuff is excellent quality at a reasonable price. You could give him a call to make sure you get exactly what you want. That’s the way I’d go if it was my Penobscot.
Usually people just replace the cane that covers the seat frame. There is a spline that holds it in place. YOu can find the exact pattern as the originals. Northwoods Canoe in Maine has good replacement parts for OT.