The 5010 is hdmi, but if you don't know what is currently plugged into the existing pj, it's kinda hard to help you. The mount you currently have most likely won't work on the new pj, unless it's a universal type then it might, so you'll have to deal with that. Running a hdmi cable can be easy if you don't have to route it through ceilings or walls. If the cable run is going to be over 20', make sure to get a good 22 awg cable, or look into Red Mere at monoprice.com.
If your old pj was connected with a DVI cable, (DVI-I input stated in the specs), then you could try using the existing cable and just add dvi-hdmi adapters on either end. Then just deal with the actual mounting of the pj. Mounting the pj isn't such a big deal, but easier with 2 people, and some knowledge before hand. The good thing is the 5010 has "lens shift" and as long as the pj is fairly centered in the top/middle of the screen, and leveled properly, the zoom and lens shift knobs will easily adjust the picture onto the screen.