Gentlemen

I've built about a dozen Curares for SPA. I have never changed the anhedral in the stab because I don't know what it will do. I have messed with dihedral in the wing. DON'T. Hans and Hanno worked out the dihedral. Reducing it creates mix issues that will not be present if the wing is built according to plans.

For SPA, balance can become an issue when using a 4-stroke. You'll need to plan for some servos in the rear. Moving the wing just a little, an inch or a bit less, forward, can allow the radio gear to go in the wing saddle.

Use any heavier wood you have to build the tail. You'll get a little more strength which is not critical and you can move weight rearward.

If you are using foam cores and don't cut your own, Don Turnock at Eureka does great work and can make a foam turtledeck for you, too. The TD saves about 5 ozs in total weight and a lot of carving and sanding.