Kurt, you've received some pretty good advice on this subject so far. I know that Mike does very nice work and Charlie (aka Wts) is right about the 90 deg cutters so their advice should have some weight. I personally use Doiron carbide cutters for my work, mostly the 75 deg but some 90 deg. Unfortunately those cutters are VERY hard to get now because Doiron seems to not care. The Dembart tools are ok if you don't do much checkering but I don't enjoy changing tips, in fact I hate it.
I personally would use either the 60 or 75 deg S1 type cutter in a pull stroke as Mike suggested and just follow the lines. It can be done if you have a steady hand and take your time. It would also be nice if you had a small veiner tool to finish up to the border but its not entirely needed.
One thing to keep in mind with these so called "flat top" checkering patterns on older lower grade American guns is that they were not true english flat top. These patters were more like regular checkering that was not finished to a true point. True english flat top is very different and very difficult to do properly.
Ok, now for my rant of the day! If anyone decides to take up checkering they NEED a checkering cradle and a vise to hold it in. I know, I know, there are a lot of people that say use sand bags or whatever but that just doesn't do it for me. BTW, the current crop of cradles available are not very good and I'll just leave it at that. Make your own! I'm making a new one now for a student/friend that wants to learn how to checker and I promise to take pictures,give a bill of materials and measurements when its finished. I'm not saying that this is the only way to build a cradle but the one that I use has worked very well for me over the last 15 - 20 years.
Just so you know I'm not trying to "blow sunshine up your rear" I'm posting a picture of some checkering that I recently finished on a Remington 1894. This pattern was copied from a EE grade Remington with some small changes so if you don't like it blame Remington.
Anyway here is the picture.