A system (100, 1000) for delivering a self-expanding implant within a body lumen, the system comprising: a tubular catheter having proximal and distal ends and comprising an interlocking outer member (500, 500', 500", 1005) slidably disposed about an interlocking inner member, a sidewall of the interlocking outer member defining a rapid exchange port; the self-expanding implant (300, 300') disposed intermediate the interlocking inner and outer members (400, 500, 500', 500", 1005); a guidewire lumen extending at least partially through each of the interlocking inner member and the interlocking outer member (500, 500', 500", 1005), the guidewire lumen being configured to align with the RX port; a push wire; and an alignment mechanism wherein the interlocking inner member has an interlock portion, and a proximal end of the implant (300, 300') has an interlock tab portion configured to mate with the interlock portion to maintain rotational alignment between the implant (300, 300') and the interlocking inner member, the alignment mechanism comprising a contact surface disposed about an inner circumference of the interlocking outer member (500, 500', 500", 1005), the inner circumference being in frictional contact with at least a portion of the implant (300, 300') to maintain rotational alignment of the interlocking outer member (500, 500', 500", 1005) relative to the interlocking inner member, thereby maintaining alignment between the guidewire lumen and the RX port, and wherein the alignment mechanism further comprises a guidewire lumen extension coupled to the interlocking inner member and communicating with the portion of the guidewire lumen extending at least partially through the interlocking inner member. a tubular catheter having proximal and distal ends and comprising an interlocking outer member (500, 500', 500", 1005) slidably disposed about an interlocking inner member, a sidewall of the interlocking outer member defining a rapid exchange port; the self-expanding implant (300, 300') disposed intermediate the interlocking inner and outer members (400, 500, 500', 500", 1005); a guidewire lumen extending at least partially through each of the interlocking inner member and the interlocking outer member (500, 500', 500", 1005), the guidewire lumen being configured to align with the RX port; a push wire; and an alignment mechanism wherein the interlocking inner member has an interlock portion, and a proximal end of the implant (300, 300') has an interlock tab portion configured to mate with the interlock portion to maintain rotational alignment between the implant (300, 300') and the interlocking inner member, the alignment mechanism comprising a contact surface disposed about an inner circumference of the interlocking outer member (500, 500', 500", 1005), the inner circumference being in frictional contact with at least a portion of the implant (300, 300') to maintain rotational alignment of the interlocking outer member (500, 500', 500", 1005) relative to the interlocking inner member, thereby maintaining alignment between the guidewire lumen and the RX port, and wherein the alignment mechanism further comprises a guidewire lumen extension coupled to the interlocking inner member and communicating with the portion of the guidewire lumen extending at least partially through the interlocking inner member.