Tilling mostly oak leaves with aged horse manure

I have found a good source for horse manure. An Equine training ranch near me.

They have large piles of manure and I plan on starting with about 3 yards or so.

My goal is to till that in to an area that is 30 feet wide by about 90 feet long along with about 2 to 3 inches of mostly rotted oak leaves.

This will be the last time I till this area.

I plan to till by the end of November and begin to harvest lettuce in May.

Is this a long enough time for soil pathogens to not be a concern?

growing up in ohio where the soil is mostly clay, what has worked well for us to start a garden plot area is mow the area short, spread a light layer (less than an inch) of sand on top of that, roto till it shallow to scratch the surface up. then add 3, or 4" layer of 2 to 3 year old manure on top, let it dry out a week & till it in and then set over winter. should be ready in spring for planting. if you have less clay then skip the sand.

Is the manure well aged?  If not it can burn plants.

There is also a concern with horse manure being contaminated.

Put the manure in your compost pile and turn it in to compost is s preferred method.

From now until May may not be a long enough to kill pathogens.

The USDA has a rule that says it should be at least 120 days between application of raw animal manure and harvest, for a plant like lettuce.
So I think you will be fine.