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Just a quick note. Benson uses Darton sleeves. It's their sleeving process that you spend your money on. There are a couple companies I would trust sleeving my block. Golden Eagle, AEBS, Benson, Darton and ERL Performance.
* Golden Eagle Mfg.
* AEBS
* Benson
* ERL Performance
These companies have different configurations for different setups and blocks. Some are closed, some are open, etc.