Adding manure will lower soil pH, but not dramatically. Adding compost will improve the tilth of your soil, however, it takes some effort to mix heavy clay soil with compost. We also have clay soil, & I add compost made from tree leaves, every spring. I wait for the soil to dry out, and break up the clay with a garden fork. I have also used a 4 prong tool that is twisted, using both hands on a double handle. Sorry, I can't remember the name of this tool, but it works pretty good on heavy clay. After the clay has been broken up, I dump on some compost, typically 5 gallons per 20 square feet, and mix it in, thoroughly. A rototiller would be helpful, but I do this manually. Phosphorus is an essential plant nutrient, and I doubt that your level of P is so high that it would be toxic to your raspberries. They will use it up, over time. Any source of organic matter will improve your soil. Compost made from tree leaves, or pine needles, pine bark fines, or peat moss. I have been working on our garden plot for 15 years, and the soil is much more easily worked, now. After the raspberries are established, you can add a thick layer of shredded tree leaves in the fall. I cover our raspberry bed with about 8 inches of shredded leaves every fall, and they are gone by the following September. I think that the worms come up at night, and eat the leaves, but I have not actually caught them in the act.

I was really shock once I saw to much Phosphorus. It says I have 120 pounds per acres and It's an excessive amount and I have read the to much P makes plants where they can't absorb and take up other nutrients and doesn't manure/compost increase P in soil? but I need to add something because right now half my garden is red clay I'm double digging it right now which is drainage. Thanks!