I bought the same thing. I've actually had the commercially produced stuff too in bottle and cans.
I just mixed and kegged it this week too. What I tried was chilling for 24hrs at 36 degs. Then attached the gas line on the 'out' post with 35psi going into the post. It will fit. It's a tight squeeze but it will go. Shoved the gas for 10 mins and then tried a glass. Not enough carbonation.
I've read in this forum somewhere about force carbing at 35psi for a week but serving it at beer serving pressure but you had to use 'helixes' in the drink tube to create restriction in the flow of be soda. This was for if you DIDN'T want to use 25+ ft of beer line. The helixes recreate that long beer line restriction on about 5-6ft of beer line.
I bought these:
Once I get the helixes and installed, I will report back.
I did try another glass today for lunch and it was really foamy. I served it at 35psi though. I then lowered the pressure and got another glass and it was the same. About 85% foam.
We'll see if these helixes do the trick.