Stabilizer question on TT, what's your rule of thumb

Raising them up on blocks will reduce side-side motion but you can also use stabilizer struts like BAL Lockarms or JT Strongarms to do that and will do a better job. The BAL ones can be bought as a pair only instead of 4. A pair at the rear only makes quite an improvement. If you want to see where your TT movement is and how much, watch the rear jacks close up while someone walks up/down the steps.