Noob all grain/partial mash question

Looking to try all grain/partial mash with a basic recipe. But let me start off with saying i have minimal equipment. 5 gal bottling bucket and a colander that fits very nicely inside (I can wrap a blanket around the bucket to keep it insulated.) My first question is would this work. I have a 5 gal water cooler but have not made a way to filter the grains. My recipe I wanted to try is this:

9 pounds American pale malt (2 row)
1 pound crystal 40L
adjust gravity with up to 3 lbs DME (Target OG about 1.075 for an ABV of 7.5%)

2 oz EKG hops 60 min
1 oz EKG 45
1 oz EKG 30
1 oz EKG 15
1 oz EKG at end of boil

Burton Salts Not sure of amount and do I place this in the mash I think yes)

Burton Ale yeast

So from my calcs I did 4.5 gal of water at 168 degrees add grain cover wrap sit 60 min drain adjust with more water if needed for 4 gallon boil (5 gal pot.) Measure specific gravity and adjust with DME and boil away.

So am I crazy with my limited means and experience. Have read most of DeathBrewer easy partial mash but not sure the amount of grains would work in a bag. Want to work into all grain and like idea of no sparge technique.

BTW thinking of calling it Wagon Trail Pale Ale a sort of american version of a IPA from an "historical" angle.

I don't see any reason why your mash setup couldn't work. The old reliable homebrew mash tun used to be the "bucket in a bucket" false bottom. Your idea sounds pretty similar to me. However, if you are going to do a "no sparge" mash, expect a lower efficiency. I would at least consider doing a batch sparge if I were you. Why waste good sugar? Especially if you're brewing high gravity like 1.075. Grain is cheap.....extract is not so cheap.