I am making a bookshelf with 3 degree angled sides bottom to top. Bottom and top shelves have through tenons. I cut the tenons and now need to remove the piece of waste between each tenon. I made a 3 degree tapered base for the jigsaw to sit on during the cut so the angle will match the sides, but my first cut was terrible. Not even close to straight. I set up the tapered base as a guide for the saw blade while the jigsaw rested on it at the proper angle, but my technique was crap. I think I can salvage it using a rasp and cleaning it up, but hard to maintain that line across the end of the shelf where it meets the side doing it this way and I am concerned it is now short of the other cuts...

Should I cut proud of the line with the jigsaw and do my best with the rasp to bring it to down to the line?

Thanks.

Brian