J Channel Pixels Down Jig

[Little_b]

I have seen and even done the whole jig thing with the pixels facing out, but I want to do some with them pointing down. With the holes on the adjacent side, I can't just slide the J Channel on a 1x4 and use a dowel to space the holes evenly. Does anyone have a reference, or idea on how to make a simple jig for this? Hope this makes sense.

i
i
i ii
i i -on this side
i___i

 

[Braveit1]

Why not? just slide the J-Channel over an L-shapped jig. Or just hang the J-Channel vertically. (My J-Channel is drilled at the top and they point down on my soffits. )