I also started with 7.5 gal turkey fryer.
Now I will tell you that it is too small for 5 gal batch.
I need to have 8 gal wort when I do 5 gal batch.
SO if you are buying a new kettle, buy at least 10 gal pot.
And Spigot is essential.
It’s too small if you do a full boil. When I started AG, I used a .5 gal. kettle, did a higher gravity boil, and topped off afterwards. It wasn’t ideal, but it worked fine. Fortunately, after a few batches that way, a friend who was getting out of brewing gave me a converted keg.
Well-I have decided simply to try the partial mash approach first. I made a “mash tun” out of two gallon cooler. I am brewing right now. It was exciting to see how things work. I used 165 degree-5.5qts of water and added my 4lbs of grain-hit 154 degrees perfectly. It is now resting. I have made contact with another brewer here in town that makes 30 gallon all grain batches. I will met up with him next weekend. My homebrew shop will start carrying Wyeast 1450 so when I switch to all grain I will go with the Denny’s Rye IPA. Here are the two articles that I used for where I am today. Thanks to all for your advice.
http://www.homebrewtalk.com/wiki/index.php/Making_a_Partial_Mash_mash_tun
http://www.byo.com/component/resource/article/511-countertop-partial-mashing
Great news.
As someone else said.
JUST BREW IT 
All grain is not that difficult at all.
Okay-first experiment over (at least brewday). I missed the mark. Expected OG was 1.045 and I hit 1.042. This recipe called for the late addition of the liquid extract (45 minutes into the boil). I had difficulty getting the boil going again (5 gallons on a stove top). I had a 2L starter (on a stirpate-very active) so the fermentation should be fine. My guess is a very love ABV beer with perhaps some chill haze. I feel good about the partial mash though and look forward to experimenting further.
I’d consider aiming for 1.045 and hitting 1.042 to be pretty successful actually.
Just picked up a 70qt Coleman extreme for $36. Heading towards all grain.
Good luck converting it into a mashtun. That’s a good size for doing 10 gallon batches. I first used Denny’s SS braided hose setup, but went to using a 1/2" SS Kewler Kitz spigot/bulkhead with straight Bazooka screen for filtration and prefer that.