I find the easiest way to do rectal is to empty capsule into c.5ml of warm water and use a kids medicine syringe

I think there is a thread specifically for rectal administration. I don't remember if it's under bo category or pm category of threads. 

I do vaguely remember that if done rectally it is much much more potent, so most people find they don't need to use the full dose they would have taken orally. 

For example if you use one capsule orally you may find you only need to use half the capsules powder when done rectally, per administration.

How to make 8 suppositories with the same amount of "stuff" in each:
1) Fill a cup that grows wider towards the top with water to say 70%
2) Put that in to your fridge and let the water freeze.
3) Dissolve the "stuff" in coconut oil and use a milk frother to stir the mixture from time to time.
4) Let the mixture cool down close to its "freezing temperature".
5) Use the milk frother again.
6) Pour this mixture on top of the ice from point 1 and 2.
7) Put the cup back into the freezer.
8) After some time get the cup containing the frozen mixture and ice underneath out of the freezer an get the disc of coconut oil + stuff out. It should drop out easily.
9) Put the cup with the ice back into the freezer for re-use and the coconut- oil disc  into the fridge.
10) Once the disc has "warmed" to fridge temperature, cut it into 8 equal sized pieces. These are you perfect sized supposiitories with the same amount of "stuff" in each.
      These pieces look edgy, but coconut oil ad fridge temperature is so soft ( and melts so fast in contact with your body), that there is no problem.
I had so much fun while working that out that I had to share it. :-)