shocks for a 5 lug readylift kit

I have a readylift sst for my 2011 5 lug tacoma. Since ill be working on the suspension i want to upgrade my shocks.
Front kit is 2.75 and it will use the spacer on top, so ill go stock size and get bilstein 4600
Rear is AAL 1.75 and heres where im not sure what to install. Do i do the same 4600 or would it be 5100 ? I plan on doing some dirt roads, a little mud here and there but mostly will be a mall crawler.

thanks for any input!!!