Ok dude, its easy you just add 1/4c to gas tank before you fill up with e85.
Why would you need to raise compression with a rebuild, then you would not have the ability to use both petrol/e85 and LP? The computer is flashed to advance the timing when you do use LP for a much more efficient burn. Sure you lose 5% power but you gain soooo much more with LP.
Thanks dude, have a good one dude, and google is your friend dude.
EDIT Dude:
Heres used trucks for reference.
http://phoenix.craigslist.org/cph/cto/2957119736.html
http://phoenix.craigslist.org/evl/cto/2956847771.html
http://phoenix.craigslist.org/wvl/cto/2909516376.html
http://phoenix.craigslist.org/wvl/cto/2947382714.html
http://phoenix.craigslist.org/wvl/cto/2892440674.html
Now back on topic to e85.................dude