Thanks dino for this great contribution to the community!
In the mean time I still haven't gotten to piggybacking the chips and installing the rotary switch due to other projects and lack of time.
But this is now getting priority. 
The best of luck with the modding to all of you!
I most definately may not take total credit for the mod. Govmnt_Lacky played a huge role as well. Much of the "XP-ALL" grunt work was done by him, with me providing code, thoughts, and at times, cheerleading

.
Anyhow, we're slowly putting together a build paper for the XP-ALL, so as anyone who wants to do the build, may do so. Without falling into the pitfalls we did! The paper will concentrate on the complete conversion. We figured that anyone with skills enough to tackle the complete conversion, should be able to do a reduced build i.e. XP-100/XP-300 only. In any case, we're always here to field questions.
If I may boast, we did figure out how to switch between modes WITHOUT having to power down the unit. This was a major coup for us, putting our version ahead of the Jetpack versions. I'm not one to toot a horn, but we were very happy about this one.

As soon as the paper is complete, I'll post, and upload it to the Gallery.