If the openings on the SLP-05 for the 6SN7 tubes are as I would suspect the same as on an SLP-98P they will not fit. No more than a 1/16 of an inch clearance for a standard tube base. Cary designed them for estetics so the tube is seen not the base. The sockets can be swapped out (and upraded at the same time) to be flush with the top of the pre so you could use the black treasure tubes but if you cant perform it yourself it would make trying the tubes more costly. I doubt very much if its a matter of removing the stand offs in between the socket and the top of the pre without actually changing the socket for its different mounting design.
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