Suspicious minds want to know: How did Elvis rock Radio City last month?

Anyone who’s ever attended a concert knows that inspecting the merchandise stands is a vital part of the live-show ritual. That was never more mandatory than on March 19 at New York’s Radio City Music Hall, where vendors hawked T-shirts with the most surreal imprint in the history of rock souvenirs: ”Elvis the Concert 1998 Tour.”

The shirts did not lie. Standing on stage before ersatz-Graceland gates, local DJ Bruce ”Cousin Brucie” Morrow informed the audience, ”You’re in for something different — unlike anything you’ve ever seen.” He wasn’t whistling ”Love Me Tender.” The house lights dimmed, and Presley’s road band from the ’70s, looking heftier and grayer, launched into ”Also Sprach Zarathustra,” the King’s standard concert opener from that era. When they segued into the boogie riff of ”See See Rider,” the nearly sold-out crowd began cheering, and out strode…Elvis.

More or less, anyway: Presley, jammed into one of his white spangled karate suits, was seen on a huge, door-shaped video screen hanging center stage, above the musicians. In the most ghoulish offshoot to date of the Dead Elvis industry, the concert — the next-to-last stop on an eight-city East Coast tour — presented Presley’s reunited band playing live to vintage performance footage of the King. (It was live and Memorex.) As if the first three months of this year haven’t been surreal enough — from Zippergate to the state funeral for Sonny Bono — leave it to Elvis to return and top it all.

As a theatrical presentation, ”Elvis: the Concert” was neither as monumentally tacky nor as technically awe inspiring as it could have been. Throughout the two-hour show, the band — including guitarist James Burton, drummer Ronnie Tutt, and pianist Glen D. Hardin — and the gospel-empowered singers the Sweet Inspirations did an able job of re-creating their parts, and the live/video interaction was always in synch. Only God (or Elvis) knows what was going through the musicians’ minds, but they smiled gamely and proved they’re still capable of deep-fried grooves. At the very least, everyone on stage gets points for maintaining a collective straight face during ”How Great Thou Art,” for which there was apparently no available footage. Instead, they played to screen projections of heavenly clouds.

Technically speaking, it was Elvis who was wanting. The clips — film and video from various concerts and TV specials between 1968 and 1973, with an ever-shifting array of outfits and sideburns — varied wildly. Many were blurry or grainy, making the dislocation between Presley and the band even more glaring. Yet, in a strange way, the marred clips only made the power of Presley’s charisma that much more dazzling. Even in such a macabre setting, even when overexposed film occasionally blotted him out, it was impossible not to watch. During those pre-bloat years, Elvis looked magnificent, like a bronzed stallion in bell-bottoms. And when he snarled through James Taylor’s macho parody ”Steamroller Blues” or dropped to the floor during ”Suspicious Minds,” it was easy to feel what it was like to attend one of his concerts. Curiously, rock’s first sex god now seems almost subdued. Compared with the up-front bumping and grinding of the pre-enlightened Madonna or even Boyz II Men, Elvis’ stage moves — a shaking thigh here, a smoldering leer there