HLP 4663 light engine replacement

[hanzi]

I just replaced the color wheel on my set. But the new unit is just as bad as the one replaced same noise and repeated starts before picture comes up. I did not get this at DM so I am trying to get this exchanged. Anyway while doing this I cleaned the inside of the set and I wiped the projector lens wit isop.alcohol and this smeared the surface, the lens is not glass. I was able to polish this back to where it was clear but there are still some smudges when on the picture. So I would like to replace this.

I do not think this lens is available by itself, - would this be part of the light engine?
Can I replace the light engine and what does this take to do - step by step instructions?

I appreciate any help on this.