I gave this some thought over the night, and here's what I came up with.
Can this be accomplished successfully?
Yes I believe it can.
Do you accept the challenge?
Yes
Where do you start?
St Augustine Florida
What route do you take?
A Southern route. From St. Augustine, westward over the peninsula of Florida and once over that, hug the coast line of the Gulf of Mexico to the Rio Grande. Once there, up the Rio Grande to central New Mexico, then take a left turn at Albuquerque
and over the central part of New Mexico and the North Central part of Arizona, to the Colorado river. Down that to the Sea of Cortez and over the Baja and into So Cal.
Where do you plan to finish?
Southern California
How long do you think it will take you?
I plan on 900 days (about 2 1/2 years)
What is in your field gear?
Without getting too much in depth, seeing that most is already listed in other posts, A small mask, fin and snorkel set, along with a Hawaiian sling (pole spear) with several tips. 550 cord. 200' of rope, along with some, not much, mountaineering equipment. My handy dandy
Leatherman Super Tool.
What modern items are critical, and what items from the period will work for you?
Modern: On the PDA a Topo map of the route I would take. Also on the PDA, a Spanish/English, French/English and the local tribes along the route language/English dictionaries. Also several chapters from the STP 31-18-SM-TC field manual.
My Woobie.
Period: Ball, cap and powder, along with a long rifle.
What are your priorities?
Staying alive and collecting 10 million dollars.
What firearms will you take?
From today, a 1911 Colt .45 (tried and tested time and time again, and with some great stopping power.)
I would acquire a long rifle, once there.
How much ammo, accessories, etc.?
150 rounds of .45 for the Colt, along with a cleaning kit and spare parts kit. 10 extra magazines.
What edged tools do you take?
My handy dandy
Leatherman Super Tool. A 20' machete. A Hersey T-3. A hand ax. An E-tool.
What navigational aids do you take?
Compass. Sextant. Topo map on the PDA, along with hard copies in case the PDA goes T.U.
What do you think your odds are of successfully completing this journey?
100%
What do you do in the 30 days before you leave?
Travel the route I would take, looking for possible hazards and obstacles that might still be around 300 years later. Research the weather from that time period and see if there are any storms, flooding or droughts as I where to move westward. Any major historical events that took place among the Europeans and local indigs, and avoid them if deemed hazardous.