You don't need an MSD on a slant, unless it is really radical. I run a homemade HEI, much less money. Spark is almost a large as MSD. Also a lot of people do not realize this, but the MSD only has multi spark below 3,000 rpm. I did try back to back comparison on my 66 Valiant, HEI to MSD 6AL, no difference in 1/4 mile performance. MSD close to $200 without oil, HEI about $40 including coil.