Just got done building a 355 with double hump steel heads, I was going to run a # 26 autolite spark plug. Now the problem is that the autolite #26 plug has a tapered seat, my heads are not tapered seat heads. Any suggestions?, I'm on a budget. I'm running a .040 piston that's 11.5 -1 compression. 206 intake 160 exhaust, solid lift cam, 750 cfm holley. Going to be running on a 3/8 mile banked dirt track, in a limited late model. Any advise would be helpful, Thanks in advance.