I assume most people mask off the front and sides so they don't end up with their receiver permanently attached to their stock. Obviously, if you had to choose between the front and back, you'd want the back of the lug bedded. If both front and back were bedded I assume that wouldn't leave you with much room to work with during assembly/disassembly. Have you ever had any issues releasing the receiver after bedding the front and back as described?
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