Other GM engines that use positive rotators on the exhaust valves use a slightly shorter valve spring on the exhaust- - - - -about 1/8", IIRC, to compensate for the thickness of the rotator. Don't some of the 261's have a similar arrangement?
Jerry


"It is better to be silent and be thought a fool than to speak and eliminate all doubt!" - Abraham Lincoln
Cringe and wail in fear, Eloi- - - - -we Morlocks are on the hunt!
There is nothing noble in being superior to your fellow man; true nobility is being superior to your former self. - Ernest Hemingway
Love your enemies and drive 'em nuts!