I'd like to join 5/4 boards end to end and am wondering about making
finger joints. There are many router bits available and I'd like some
input of their use. How easy is it to get the board surfaces to be in
the same plane? Lots of adjusting and shimming or does it just
happen? Can it be done with a hand held router? (I've got a router
table but I'll be working with lengths of 8 feet or so which may be
difficult to handle on a router table. (The end result will be
painted, so some blemishes are acceptable)

For the curious, I'm replacing some of the trim boards on my house
that have rotted at the end(s) because no caulk was applied when
installed 15 years ago and I figure it will be cheaper to cut off the
rot and splice a new section than to replace the entire board. 5/4
stock is not cheap! Of course, a scarf joint is a possibility but it
seems as if a finger joint may be the way to go.

Thanks in advance.