I've seen guides worn out due to too good a seal! If the umbrella seals are used, then the original O ring below the keeper and the sheet metal shroud under the spring retainer should be left off. (I've worked so many V-8's and 250/292's I don't remember if the 235's have the same arrangement.) It's possible to starve the guides for oil enough to create rapid wear, especially on the exhausts. Once the oil starts to gravity-flow down the exhaust guides, oil consumption increases dramatically. If you're using a quart in 300 miles, umbrella seals will help a little, but not much.
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!