I grew up 20 minutes from the ramp, so never needed a guide. I can recommend a great place to eat some good ole southern cookin' tho: Top O' River Catfish & Seafood Restaurant Its awesome, and youll have to-go plates for days. Check it out, most plates are less than $15, and theres no way you can eat it all.
I hear all these stories about every bass in that lake being over 4lbs, but trust me, its no Dream Lake. You have to work hard to catch fish there just like anywhere else. There is a common misconception that the bass there just practically jump in the boat and bite anything, but its tough, especially in these months. Prepare for windy fishing in around 60 degree weather, and pray you get a good week of decent weather before you go. The water temps need to get above 50 degrees before things turn on, and we've had a cold winter. You should be hitting it just about right though during that timeframe.
Gunterville is a great lake, the best public lake other than Okeechobee IMO, and with a little reseach and a good guide, you should be successful. Is there anyway you can delay your trip about a month?
I dont know if youre interested but Gunterville produces some 40+ pound stripers and 100+ pound catfish... I know there are guides for that.. just a thought
Good luck, have fun, and post pics!!! and try the greens at top of the river