A B737-400 WAS DISPATCHED IN NON COMPLIANCE OF THE MEL WITH #2 TANK FUEL QUANTITY INOP AND #2 TANK FORWARD BOOST PUMP LOW PRESSURE WARNING LIGHT INOP.

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ACFT X ARRIVED ZZZ WITH THE #2 FUEL QUANTITY ON MEL 28-6. DURING 'W/A' INSPECTION IT WAS NOTED THAT THE #2 TANK FORWARD BOOST PUMP LOW PRESSURE LIGHT WAS INOP. PRIOR TO DEP MAINT CTL ASKED IF I WOULD ACCEPT MEL 28-1. I CONTACTED ZZZ OPS TO SEE IF THIS WOULD HAVE AN IMPACT ON THE EXPECTED LOAD. JNU OPS SAID IT WOULD BE NO PROB. I THEN ADVISED MAINT CTL TO GO AHEAD WITH THE MEL. I ADDED THE REQUIRED AMOUNT OF FUEL PER MEL 28-1 AND THE FLT DEPARTED. THE MAINT CTLR ADVISED ME OF THE INCORRECT ASSIGNMENT OF THE MEL AFTER THE ACFT HAD LANDED IN ZZZ1. IT WAS FOUND THAT MEL 28-1B AND 28-6 WERE NOT COMPATIBLE. THERE IS NO REF IN MEL 28-1 TO ALSO REF MEL 28-6; UNFORTUNATELY I TRUSTED THAT MAINT CTL HAD ISSUED THE CORRECT MEL AND MAINT PROCS. I LOOKED AT MEL 28-1 AND ADDED THE FUEL THAT IT REQUIRED BUT FAILED TO ALSO CHK MEL 28-6 FOR ANY ANOMALIES ASSOCIATED WITH IT. ACCORDING TO MAINT CTL; NEITHER THE MANUFACTURER'S MASTER MEL OR THE DDPG (DISPATCHER MANUAL) LIST THE EXCLUSION IN MEL 28-1 IN REGARDS TO MEL 28-1; ALTHOUGH MEL 28-6 DOES LIST THE MEL 28-1 EXCLUSION. IN MY OPINION EVERY EXCLUDED MEL SHOULD BE XREFED TO THE OTHER EXCLUDED MEL TO AID IN APPLICABILITY DETERMINATION.