Changed out my aluminum angle plug vortec heads for a pair of Edelbrock etec 200 straight plug heads. 90 degree plug boots worked very well on the old heads but now the plugs on the new heads are very close to my 1 3/4" header tubes. Have looked and tried the recommended Champion RC12YC plugs and also the short Accel plugs (which are about the same length). But they are very close to the header tubes. Have found some NGK racing spark plugs R7282-9 that have a very short insulator that looks like it would work (half the length of the Champions and Accels). Has anyone tried these? Heat range could be an issue. Any down side other than the price of $50 apiece.