how to convert to partial mash

I don't really see anything here to convert to a partial mash. Normally, you would convert an All Grain recipe to partial mash, to accommodate grains in the AG recipe that shouldn't be simply steeped.

If you want to just get some experience with mashing a small amount of grain, you could delete the pound of dry extract and mini-mash your pound of caramel malt along with about 1.6 pounds of Pale Ale Malt.

 

There is no one way to do a partial mash. You have to decide what percentage of your grist you want to mash, and that decision may be based on your equipment. My first partial mash recipe was really just to test my all-grain equipment. I wanted to mash a sizeable percentage of my grist (50%) to test my efficiency, but I wanted to have a large component of extract (50%) in case my efficiency turned out to be low. One reason to do a partial mash, as Vikeman alludes to, is if you have some grains that are not readily available in extract form, that will require conversion. An example might be oatmeal for an oatmeal stout (although we have all seen recipes that suggest steeping). If you can't get Maris Otter extract, Munich extract, or rye extract (which used to not be widely available), you might want to include those grains in a partial mash.

I have never had a persimmon ale. I suspect there won't be much flavor from persimmon (I just ate one yesterday and thought to myself that it was all sugar and would ferment out, leaving no characteristic flavor behind). However, the spices in this beer make me think it would benefit from a biscuit, bready malt. I would use Maris or Munich, either in extract form or grain form, depending on my mash capabilities. Your mileage may vary.