Bill -
If the unit is currently a retro unit with a large cabinet, rear screen, etc.....then the answer is probably not. If it is a FP unit and the switches have merely been set for RP use, then the manual should contain the necessary information you need...quite simple really. If it is a FP unit, disregard the rest of this post below.
I'm very familiar with the retro 801s unit, and though have seen retro 808's I've never opened one up to inspect the contruction. The retro 801s retros are designed and built for rear projection only, and while it is physically possible to re-build one for front projection, it would be tremendously un-feasible for most to attempt to do so.
For example, the retros have short-throw liquid-coupled lenses which cannot be re-focused much beyond their original configuration. My 67" retro can go out to about 100" only. Also, the mechanical convergence adjustments are non-existent. That is, there is no way to adjust the blue and red tubes (e.g., point them more outwards via 'toe-in' or 'toe out'), so that a larger image can be projected and converged.
This I know for certain applies to the retro 801s, but I'm not certain if it is so for the 808 series, but it probably is. Some manufacturers basically 'stuff' a FP chassis with short-throw lenses into their retros. I believe there are Electrohome's that are like this.
- Chris
