The long strip of wood with paper attached is an answer

You can get rolls of 1" wide cloth sanding strips at a good wood working shop. The local one had a special on a 6 pack of 6 grits from 80 to 600 for not much. A very nice straight 1" square of Oakabout 2 to 3 ft long is a good base. Use some carpet tape and tape the strips on.

A razor plane is a must for shaping also.

I'll tell you what not to try, at least without using a lot of caution. I decided that a stripof PVCpipe cut in half and then lined on the inside with sand paper would make a great tool for shaping the LE. Iused a 1/2 round piece of pipe, and it did a very nice job off giving a long rounded edge. IT also did a great job of cutting groves in the ribs. Big ugly groves. Maybe a 1/3 rd or even 1/4 rd might be OK, but nix on the 1/2 round.

The main thing is to think hand work vs machines for this. You shape the LE after it is glued in place, so saws and power grinders are going to cause you some problems.

Last thing, Glue. CA glue works great, but leaves an edge that is almost impossible to sand. Epoxy works also, but again it is difficult to sand. Good Ole Titebond carpenters glue is a very good choice as you can sand it with minimum problems. Even Elmer's white glue.

On sanding CA, I stumbled across using 240 or 320, even 400 grit wet or dry on a hard flat stick. The wet or dry is not very good for sanding balsa, but it will do a very good job of cutting the hard CA. You will use a lot of it as it will load up quickly. I spray a full sheet of Wet or dry with spray 77 adhesive and the lay down craft sticks as tight as I can, covering the whole sheet. Then use a #11 blade and cut the paper out to the stick shape. This gives a good small tight place sanding stick, You can cut the stick for little tight places. The cost is about a penny each sanding stick so using one for a few minutes and throwing it away doesn't break the bank.

Don