You should be fine Worth those, my buddy has a 3.5 rancho on his 85 and runs 14" Bilesteins and does not come close to full travel.
The marlin kits com with 14" travel shocks and there is no way a regular 3.5" lift is going to flex as much as a Marlin lift.
If you are planning on re-ewroking your suspension in the future for more flex i would just go straight to a longer travel shock, instead of wasting your money now, and re-buying later. just my